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Zhang Y, Han X, Ren YJ, Sun HP, Xie SF, Chu XQ, Chen GF, Liu C, Xu SH. [Microwave ablation versus radiofrequency ablation for solid or predominantly solid benign thyroid nodules: a randomized controlled clinical trial]. Zhonghua Nei Ke Za Zhi 2024; 63:74-80. [PMID: 38186121 DOI: 10.3760/cma.j.cn112138-20231024-00248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Objective: To compare the short-term efficacy and the safety of microwave ablation (MWA) and radiofrequency ablation (RFA) in the treatment of benign thyroid nodules (BTNs). Methods: This prospective randomized controlled trial, performed from December 2019 to September 2021, included 36 patients with solid or predominantly solid BTNs who met the eligibility criteria and provided written informed consent at the Nanjing sub-center (Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine). Patients were assigned to either the MWA group or the RFA group (18 patients in each group) at a ratio of 1∶1 using a block randomization design and allocation concealment using sealed envelope randomization. The independent-sample t-test and χ2 test were used to compare the volume reduction rates (VRRs), effective rates (VRRs≥50%), cosmetic scores, and complication rates at 1, 3, and 6 months after treatment between the two groups. Results: The clinical characteristics of the two groups of patients were comparable. After ablation, the nodule volume was significantly reduced in both groups. At 1, 3, and 6 months, there was no significant difference in the volume between the two groups (all P>0.05). At 3 months, the RFA group had a larger VRRs than that in the MWA group (62.08%±12.46% vs. 46.90%±23.16%, t=-2.45, P=0.021). However, at 1 and 6 months, no statistical significance was observed (both P>0.05). No significant difference was observed in the effective rates at the last follow-up (14/18 vs. 18/18, P=0.104). However, the RFA group had a lower cosmetic score than that in the MWA group (1.78±0.43 vs. 2.17±0.51, t=-2.47, P=0.019). There was no statistically significant difference in the complication rates between the two groups (all P>0.05). Conclusions: Both MWA and RFA were effective and safe treatments for BTNs, with no significant differences in short-term efficacy and safety. In addition, the RFA group showed slightly more favorable outcomes than the MWA group in terms of cosmetic improvement.
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Affiliation(s)
- Y Zhang
- Endocrine and Diabetes Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - X Han
- Endocrine and Diabetes Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - Y J Ren
- Endocrine and Diabetes Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - H P Sun
- Endocrine and Diabetes Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - S F Xie
- Endocrine and Diabetes Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - X Q Chu
- Endocrine and Diabetes Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - G F Chen
- Endocrine and Diabetes Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - C Liu
- Endocrine and Diabetes Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - S H Xu
- Endocrine and Diabetes Center, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
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2
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Shen JY, Shi CY, Pan ZM, Ju LL, Dong MD, Chen GF, Zhang YC, Yuan JK, Wu CJ, Xie YW, Wu J. Reentrance of interface superconductivity in a high-T c cuprate heterostructure. Nat Commun 2023; 14:7290. [PMID: 37949854 PMCID: PMC10638369 DOI: 10.1038/s41467-023-42903-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Accepted: 10/25/2023] [Indexed: 11/12/2023] Open
Abstract
Increasing the carrier density in a Mott insulator by chemical doping gives rise to a generic superconducting dome in high temperature superconductors. An intriguing question is whether a second superconducting dome may exist at higher dopings. Here we heavily overdope La2-xSrxCuO4 (0.45 ≤ x ≤ 1.0) and discover an unprecedented reentrance of interface superconductivity in La2-xSrxCuO4 /La2CuO4 heterostructures. As x increases, the superconductivity is weakened and completely fades away at x = 0.8; but it revives at higher doping and fully recovers at x = 1.0. This is shown to be correlated with the suppression of the interfacial charge transfer around x = 0.8 and the weak-to-strong localization crossover in the La2-xSrxCuO4 layer. We further construct a theoretical model to account for the sophisticated relation between charge localization and interfacial charge transfer. Our work advances both the search for and control of new superconducting heterostructures.
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Affiliation(s)
- J Y Shen
- School of Physics, Zhejiang University, Hangzhou, 310027, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, 310024, China
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, China
| | - C Y Shi
- School of Physics, Zhejiang University, Hangzhou, 310027, China
| | - Z M Pan
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
| | - L L Ju
- School of Physics, Zhejiang University, Hangzhou, 310027, China
| | - M D Dong
- School of Physics, Zhejiang University, Hangzhou, 310027, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, 310024, China
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, China
| | - G F Chen
- School of Physics, Zhejiang University, Hangzhou, 310027, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, 310024, China
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, China
| | - Y C Zhang
- School of Physics, Zhejiang University, Hangzhou, 310027, China
- Research Center for Industries of the Future, Westlake University, Hangzhou, 310024, China
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, China
| | - J K Yuan
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
| | - C J Wu
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, China
- New Cornerstone Science Laboratory, Department of Physics, School of Science, Westlake University, 310024, Hangzhou, China
- Institute for Theoretical Sciences, Westlake University, Hangzhou, 310024, Zhejiang, China
- Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou, 310024, Zhejiang, China
| | - Y W Xie
- School of Physics, Zhejiang University, Hangzhou, 310027, China
| | - J Wu
- Research Center for Industries of the Future, Westlake University, Hangzhou, 310024, China.
- Department of Physics, School of Science, Westlake University, Hangzhou, 310024, China.
- Key Laboratory for Quantum Materials of Zhejiang Province, School of Science, Westlake University, Hangzhou, 310024, China.
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3
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Chen HS, Yang Y, Ni J, Chen GF, Ji Y, Yi F, Zhang ZB, Wu J, Cai XL, Shao B, Wang JF, Liu YF, Geng DQ, Qu XH, Li XH, Wei Y, Han SG, Zhu RX, Ding JP, Lyu H, Huang YN, Huang YH, Xiao B, Gong T, Yu XF, Cui LY. [Effects of cinepazide maleate injection on blood pressure in patients with acute ischemic stroke and hypertension]. Zhonghua Nei Ke Za Zhi 2022; 61:916-920. [PMID: 35922216 DOI: 10.3760/cma.j.cn112138-20210822-00574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Objective: To investigate the blood pressure change in patients with acute ischemic stroke (AIS) and hypertension treated with cinepazide maleate injection. Methods: This was a subgroup analysis of post-marketing clinical confirmation study of cinepazide maleate injection for acute ischemic stroke: a randomized, double-blinded, multicenter, placebo-parallel controlled trial, which conducted in China from August 2016 to February 2019. Eligible patients fulfilled the inclusive criteria of acute anterior circulation ischemic stroke with National Institutes of Health Stroke Scale (NIHSS) scores of 7-25. The primary endpoints were mean blood pressure of AIS patients treated with cinepazide maleate or control, which were assessed during the treatment period (14 days), and the proportion of the patients with normal blood pressure was analyzed after the treatment period. Furthermore, a subgroup analysis was performed to investigate a possible effect of the history of hypertension on outcomes. Results: This analysis included 809 patients with hypertension. There was no significant difference in patients blood pressure and the proportion of patients with normal blood pressure (60.5% vs. 59.0%,P>0.05) between cinepazide maleate group and control group. Conclusion: Administration of cinepazide maleate injection does not affect the management of clinical blood pressure in patients with AIS.
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Affiliation(s)
- H S Chen
- Department of Neurology, General Hospital of Northern Theater Command, Shenyang 110016, China
| | - Y Yang
- Department of Neurology, the First Bethune Hospital of Jilin University, Changchun 130021, China
| | - J Ni
- Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - G F Chen
- Department of Neurology, Xuzhou Central Hospital, Xuzhou 221009, China
| | - Y Ji
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin 300350, China
| | - F Yi
- Department of Neurology, JiangXi PingXiang People's Hospital, Pingxiang 337055, China
| | - Z B Zhang
- Department of Neurology, the Fourth Affiliated Hospital of Harbin Medical University, Harbin 150001, China
| | - J Wu
- Department of Neurology, the Second Affiliated Hospital of Nanjing Medical University, Nanjing 210011, China
| | - X L Cai
- Department of Neurology, Lishui Municipal Central Hospital, Lishui 323000, China
| | - B Shao
- Department of Neurology, the First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - J F Wang
- Department of Neurology, Dalian Municipal Central Hospital, Dalian 116033, China
| | - Y F Liu
- Department of Neurology, Huangshi Central Hospital, Huangshi 435000, China
| | - D Q Geng
- Department of Neurology, the Affiliated Hospital of Xuzhou Medical University, Xuzhou 221002, China
| | - X H Qu
- Department of Neurology, Jiangxi Provincial People's Hospital, Nanchang 330006, China
| | - X H Li
- Department of Neurology, Jinan Central Hospital, Jinan 250013, China
| | - Y Wei
- Department of Neurology, Hengshui People's Hospital (Harrison International Peace Hospital), Hengshui 053000, China
| | - S G Han
- Department of Neurology, Meihekou City Central Hospital, Meihekou 135014, China
| | - R X Zhu
- Department of Neurology, Inner Mongolia People's Hospital, Hohhot 010017, China
| | - J P Ding
- Department of Neurology, Xuanwu Hospital Capital Medical University, Beijing 100053, China
| | - H Lyu
- Department of Neurology, Shaanxi Provincial People's Hospital, Xi'an 710068, China
| | - Y N Huang
- Department of Neurology, Peking University First Hospital, Beijing 100034, China
| | - Y H Huang
- Department of Neurology, the Seventh Medical Center of the Chinese PLA General Hospital, Beijing 100700, China
| | - B Xiao
- Department of Neurology, Xiangya Hospital Central South University, Changsha 410008, China
| | - T Gong
- Department of Neurology, Beijing Hospital, Beijing 100730, China
| | - X F Yu
- Department of Neurology, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - L Y Cui
- Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
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4
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Liu ZY, Dong QX, Yang PT, Shan PF, Wang BS, Sun JP, Dun ZL, Uwatoko Y, Chen GF, Dong XL, Zhao ZX, Cheng JG. Pressure-Induced Superconductivity up to 9 K in the Quasi-One-Dimensional KMn_{6}Bi_{5}. Phys Rev Lett 2022; 128:187001. [PMID: 35594110 DOI: 10.1103/physrevlett.128.187001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 03/13/2022] [Accepted: 04/07/2022] [Indexed: 06/15/2023]
Abstract
The Mn-based superconductor is rare owing to the strong magnetic pair-breaking effect. Here we report on the discovery of pressure-induced superconductivity in KMn_{6}Bi_{5}, which becomes the first ternary Mn-based superconductor. At ambient pressure, the quasi-one-dimensional KMn_{6}Bi_{5} is an antiferromagnetic metal with T_{N}≈75 K. By measuring resistance and ac magnetic susceptibility under hydrostatic pressures up to 14.2 GPa in a cubic anvil cell apparatus, we find that its antiferromagnetic transition can be suppressed completely at a critical pressure of P_{c}≈13 GPa, around which bulk superconductivity emerges and displays a superconducting dome with the maximal T_{c}^{onset}=9.3 K achieved at about 14 GPa. The close proximity of superconductivity to a magnetic instability in the temperature-pressure phase diagram of KMn_{6}Bi_{5} and an unusually large μ_{0}H_{c2}(0) exceeding the Pauli paramagnetic limit suggests an unconventional magnetism-mediated paring mechanism. In contrast to the binary MnP, the flexibility of the crystal structure and chemical compositions in the ternary AMn_{6}Bi_{5} (A=alkali metal) can open a new avenue for finding more Mn-based superconductors.
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Affiliation(s)
- Z Y Liu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Q X Dong
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - P T Yang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - P F Shan
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - B S Wang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - J P Sun
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Z L Dun
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Y Uwatoko
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - G F Chen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - X L Dong
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Z X Zhao
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - J-G Cheng
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
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5
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Lee MC, Sirica N, Teitelbaum SW, Maznev A, Pezeril T, Tutchton R, Krapivin V, de la Pena GA, Huang Y, Zhao LX, Chen GF, Xu B, Yang R, Shi J, Zhu JX, Yarotski DA, Qiu XG, Nelson KA, Trigo M, Reis DA, Prasankumar RP. Direct Observation of Coherent Longitudinal and Shear Acoustic Phonons in TaAs Using Ultrafast X-Ray Diffraction. Phys Rev Lett 2022; 128:155301. [PMID: 35499894 DOI: 10.1103/physrevlett.128.155301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 01/19/2022] [Accepted: 02/25/2022] [Indexed: 06/14/2023]
Abstract
Using femtosecond time-resolved x-ray diffraction, we investigated optically excited coherent acoustic phonons in the Weyl semimetal TaAs. The low symmetry of the (112) surface probed in our experiment enables the simultaneous excitation of longitudinal and shear acoustic modes, whose dispersion closely matches our simulations. We observed an asymmetry in the spectral line shape of the longitudinal mode that is notably absent from the shear mode, suggesting a time-dependent frequency chirp that is likely driven by photoinduced carrier diffusion. We argue on the basis of symmetry that these acoustic deformations can transiently alter the electronic structure near the Weyl points and support this with model calculations. Our study underscores the benefit of using off-axis crystal orientations when optically exciting acoustic deformations in topological semimetals, allowing one to transiently change their crystal and electronic structures.
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Affiliation(s)
- Min-Cheol Lee
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - N Sirica
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - S W Teitelbaum
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - A Maznev
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA
- Institute for Soldier Nanotechnology, Massachusetts Institute of Technology, 500 Technology Square, NE47-598, Cambridge, Massachusetts, 02139, USA
| | - T Pezeril
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA
- Institut de Physique de Rennes, Université de Rennes 1, UMR CNRS 6251, 35000 Rennes, France
| | - R Tutchton
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - V Krapivin
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA
| | - G A de la Pena
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Y Huang
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA
| | - L X Zhao
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - G F Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - B Xu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - R Yang
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - J Shi
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA
| | - J-X Zhu
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - D A Yarotski
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - X G Qiu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - K A Nelson
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA
- Institute for Soldier Nanotechnology, Massachusetts Institute of Technology, 500 Technology Square, NE47-598, Cambridge, Massachusetts, 02139, USA
| | - M Trigo
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - D A Reis
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Department of Applied Physics, Stanford University, Stanford, California 94305, USA
- Department of Photon Science, Stanford University, Stanford, California 94305, USA
| | - R P Prasankumar
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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6
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Sirica N, Orth PP, Scheurer MS, Dai YM, Lee MC, Padmanabhan P, Mix LT, Teitelbaum SW, Trigo M, Zhao LX, Chen GF, Xu B, Yang R, Shen B, Hu C, Lee CC, Lin H, Cochran TA, Trugman SA, Zhu JX, Hasan MZ, Ni N, Qiu XG, Taylor AJ, Yarotski DA, Prasankumar RP. Photocurrent-driven transient symmetry breaking in the Weyl semimetal TaAs. Nat Mater 2022; 21:62-66. [PMID: 34750539 DOI: 10.1038/s41563-021-01126-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 09/08/2021] [Indexed: 06/13/2023]
Abstract
Symmetry plays a central role in conventional and topological phases of matter, making the ability to optically drive symmetry changes a critical step in developing future technologies that rely on such control. Topological materials, like topological semimetals, are particularly sensitive to a breaking or restoring of time-reversal and crystalline symmetries, which affect both bulk and surface electronic states. While previous studies have focused on controlling symmetry via coupling to the crystal lattice, we demonstrate here an all-electronic mechanism based on photocurrent generation. Using second harmonic generation spectroscopy as a sensitive probe of symmetry changes, we observe an ultrafast breaking of time-reversal and spatial symmetries following femtosecond optical excitation in the prototypical type-I Weyl semimetal TaAs. Our results show that optically driven photocurrents can be tailored to explicitly break electronic symmetry in a generic fashion, opening up the possibility of driving phase transitions between symmetry-protected states on ultrafast timescales.
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Affiliation(s)
- N Sirica
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, USA.
| | - P P Orth
- Ames Laboratory, Ames, IA, USA
- Department of Physics and Astronomy, Iowa State University, Ames, IA, USA
| | - M S Scheurer
- Institute for Theoretical Physics, University of Innsbruck, Innsbruck, Austria
| | - Y M Dai
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, USA
- Center for Superconducting Physics and Materials, National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing, China
| | - M-C Lee
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - P Padmanabhan
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - L T Mix
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - S W Teitelbaum
- Department of Physics, Arizona State Univeristy, Tempe, AZ, USA
- Beus CXFEL Labs, Biodesign Institute, Arizona State Univeristy, Tempe, AZ, USA
| | - M Trigo
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, USA
| | - L X Zhao
- Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - G F Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - B Xu
- Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - R Yang
- Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - B Shen
- Department of Physics and Astronomy, University of California, Los Angeles, CA, USA
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics, Guangzhou, China
| | - C Hu
- Department of Physics and Astronomy, University of California, Los Angeles, CA, USA
| | - C-C Lee
- Department of Physics, Tamkang University, New Taipei, Taiwan
| | - H Lin
- Institute of Physics, Academia Sinica, Taipei, Taiwan
| | - T A Cochran
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, USA
| | - S A Trugman
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - J-X Zhu
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - M Z Hasan
- Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, NJ, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - N Ni
- Department of Physics and Astronomy, University of California, Los Angeles, CA, USA
| | - X G Qiu
- Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - A J Taylor
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - D A Yarotski
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - R P Prasankumar
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, NM, USA.
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7
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Hu S, Li XJ, Law S, Shen CY, Yao GQ, Zhang XQ, Li J, Chen GF, Xu B, Liu XM, Ma XY, Feng K, Liu PZ. Prefrontal cortex alterations in major depressive disorder, generalized anxiety disorder and their comorbidity during a verbal fluency task assessed by multi-channel near-infrared spectroscopy. Psychiatry Res 2021; 306:114229. [PMID: 34749225 DOI: 10.1016/j.psychres.2021.114229] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 08/17/2021] [Accepted: 09/26/2021] [Indexed: 01/04/2023]
Abstract
Major depressive disorder (MDD) and generalized anxiety disorder (GAD) are frequently comorbid with each other, and both associated with substantial cognitive impairments; however, it is still unclear whether their impairments are neurobiologically similar or distinct. This study aims to investigate the cognitive functions of the prefrontal cortex (PFC) in patients with MDD and GAD during the verbal fluency task (VFT) using functional near-infrared spectroscopy (fNIRS). Fifty-two patients with MDD, fifty-one patients with GAD, fifty-two patients with the comorbidity of MDD and GAD (CMG), and forty-seven healthy controls (HC) participated in the study. Significant hypoactivation in the left ventrolateral and the left dorsolateral PFC was common in all patient groups when compared to HCs, suggesting a shared etiology. Furthermore, MDD patients showed significant hypoactivation at the right frontal pole cortex (FPoC) when compared to HCs and significant hypoactivation at the middle FPoC when compared to the CMG patients. Our work is the first fNIRS study to reveal the shared and unique neurobiological profiles of MDD, GAD and their comorbidity under the same standard experimentation condition, suggesting fNIRS holds promise as an adjutant to assist clinical diagnosis.
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Affiliation(s)
- Shuang Hu
- School of Medicine, Tsinghua University, Beijing, China
| | - Xiao-Jun Li
- School of Medicine, Tsinghua University, Beijing, China
| | - Samuel Law
- Department of Psychiatry, Faculty of Medicine, University of Toronto, Canada
| | - Chen-Yu Shen
- Department of Psychiatry, Beijing Yuquan Hospital, Tsinghua University, Beijing, China
| | - Guan-Qun Yao
- School of Medicine, Tsinghua University, Beijing, China
| | - Xiao-Qian Zhang
- Department of Psychiatry, Beijing Yuquan Hospital, Tsinghua University, Beijing, China
| | - Juan Li
- School of Medicine, Tsinghua University, Beijing, China; Department of Psychiatry, Beijing Yuquan Hospital, Tsinghua University, Beijing, China
| | - Gui-Fang Chen
- School of Medicine, Tsinghua University, Beijing, China; Department of Psychiatry, Beijing Yuquan Hospital, Tsinghua University, Beijing, China
| | - Bo Xu
- Department of Psychiatry, Beijing Yuquan Hospital, Tsinghua University, Beijing, China
| | - Xiao-Min Liu
- Department of Neurology and Psychiatry, Beijing Shijitan Hospital, Capital Medical University, Beijing, China
| | - Xiang-Yun Ma
- Beijing Sixth Hospital, Peking University, Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health, National Clinical Research Center for Mental Disorders, Beijing, China
| | - Kun Feng
- Department of Psychiatry, Beijing Yuquan Hospital, Tsinghua University, Beijing, China.
| | - Po-Zi Liu
- School of Medicine, Tsinghua University, Beijing, China; Department of Psychiatry, Beijing Yuquan Hospital, Tsinghua University, Beijing, China.
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Ni WJ, Chu XQ, Lu CY, Chen GF, Han X, Xu Y, Wu XP, Wang JH, Liu C, Xu SH. [Effectiveness and safety of ultrasound-guided microwave ablation for the treatment of primary hyperparathyroidism in 12 patients with parathyroid adenoma]. Zhonghua Nei Ke Za Zhi 2021; 60:904-907. [PMID: 34551480 DOI: 10.3760/cma.j.cn112138-20201111-00935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
To investigate the effectiveness and safety of ultrasound-guided microwave ablation (MWA) in treatment of primary hyperparathyroidism (PHPT). A total of 12 PHPT patients with parathyroid adenoma were treated with MWA in Nanjing University of Chinese Medicine Affiliated Hospital of Integrated Traditional Chinese and Western Medicine from May 2019 to February 2021. The patients were followed up once every 3 months for 3-12 months. Levels of serum parathyroid hormone (PTH), calcium and phosphorus were detected before and 20 min, 4h and 1day after ablation, and during follow-up period. The volume and volume reduction rate of parathyroid lesion were compared before the treatment and at the end of follow-up. The technical and clinical success of MWA were assessed as well. At the end of follow-up, median serum PTH [66.60 (42.21,80.03) ng/L vs.169.90 (89.01,396.50) ng/L] and calcium [2.39 (2.32,2.49) mmol/L vs. 2.75 (2.57,2.96) mmol/L] levels in 12 patients decreased significantly (all P<0.05). A complete response in terms of PTH and calcium levels was achieved in 6 of the 12 patients, while 4 of the patients had slightly elevated PTH levels just above the upper limit of normal reference range, and 2 of the patients remained abnormal PTH and calcium levels. The clinical cure rate was 50%. The volumes of all lesion after ablation were significantly decreased (P<0.05), with the technical success rate reaching 92.3%. No serious complications were observed. Ultrasound-guided MWA, thus, is safe and effective in the treatment of PHPT.
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Affiliation(s)
- W J Ni
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - X Q Chu
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - C Y Lu
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - G F Chen
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - X Han
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - Y Xu
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - X P Wu
- Department of Ultrasound, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - J H Wang
- Department of General Surgery, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - C Liu
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
| | - S H Xu
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing 210028, China
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9
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Mao C, Chen GF, Pan YJ, Peng TL, Lyu JC. [Trend analysis and prediction of colorectal cancer morbidity and mortality of residents in urban areas of Guangzhou from 1972 to 2015]. Zhonghua Yu Fang Yi Xue Za Zhi 2021; 55:640-645. [PMID: 34034405 DOI: 10.3760/cma.j.cn112150-20200828-01164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To analyze the trend of mortality and incidence of colorectal cancer among urban residents in Guangzhou from 1972 to 2015 and to predict the mortality of colorectal cancer from 2016 to 2025. Methods: The mortality data of colorectal cancer among urban residents in Guangzhou were collected from the death registration of malignant tumors of Guangzhou Health Statistics Bureau (1972-1979), Guangzhou Health Statistics (1980-2001), Guangzhou Cancer Registration Annual Report (2002-2009) and China Cancer Registration Annual Report (2010-2015). The incidence of colorectal cancer was collected from Guangzhou Cancer Registration Annual Report (2002-2009) and China Cancer Registration Annual Report (2010-2015). The incidence and mortality data of colorectal cancer coded as C18-C21 in 10th Edition of International Classification of Diseases (ICD-10) were obtained from the above data, and the demographic data were from the Guangzhou Municipal Bureau of Statistics. Joinpoint model was used to calculate the annual change percentage (APC) and average annual change percentage (AAPC) of colorectal cancer mortality and incidence among urban residents in Guangzhou from 1972 to 2015 and from 2002 to 2015. ARIMA model was used to predict colorectal cancer mortality from 2016 to 2025. Results: There were 19 309 colorectal cancer deaths among urban residents in Guangzhou from 1972 to 2015. The crude mortality rate of colorectal cancer increased from 4.33/100 000 to 24.89/100 000 (AAPC=4.2%, P<0.001). A total of 24 033 new cases of colorectal cancer were reported in Guangzhou from 2002 to 2015. The crude incidence rate of colorectal cancer increased from 22.95/100 000 to 52.81/100 000 (AAPC=6.6%, P<0.001). The mortality rate of colorectal cancer among urban residents of Guangzhou would continuously increase from 2016 to 2025 and reach 29.53/100 000 in 2025. Conclusion: The mortality rate of colorectal cancer among urban residents of Guangzhou from 1972 to 2015 and the incidence rate of colorectal cancer from 2002 to 2015 both show an upward trend. The mortality rate will increase from 2016 to 2025.
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Affiliation(s)
- C Mao
- School of Public Health, Guangzhou Medical University, Guangzhou 511436, China
| | - G F Chen
- School of Public Health, Guangzhou Medical University, Guangzhou 511436, China
| | - Y J Pan
- School of Public Health, Guangzhou Medical University, Guangzhou 511436, China
| | - T L Peng
- Department of Gastrointestinal Surgery, the Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan 511518, China
| | - J C Lyu
- School of Public Health, Guangzhou Medical University, Guangzhou 511436, China
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10
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Chen GF, Mao MC, Feng K, Gan JC, Zhang XQ, Shen CY, Xu B, Liu XM, Ren XJ, Liu PZ, Wang Y. Brain activation during verbal fluency task in type II bipolar disorder patients: a near-infrared spectroscopy study. Psychiatry Res 2021; 298:113762. [PMID: 33545426 DOI: 10.1016/j.psychres.2021.113762] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Accepted: 01/24/2021] [Indexed: 01/09/2023]
Abstract
BACKGROUND Previous studies have shown that BD patients exhibited impairment when performing a verbal fluency task (VFT) and abnormal prefrontal cortex activation during this task. However, no study has specifically examined whether patients with type II BD demonstrate difficulty in performing VFT and impairments in relevant neural correlates or whether these are related to psychotic symptoms, the present study aimed to examine these issues. METHODS Forty-nine patients with type II BD (21 patients with psychotic symptoms [BDIIp] and 28 patients without psychotic symptoms [BDIIn]) and 45 matched healthy controls (HCs) participated the study and completed the VFTs, while their brain activity was recorded with near-infrared spectroscopy (NIRS). RESULTS Both BDIIp and BDIIn patients showed poorer performance on VFTs than HCs. In addition, BDII patients showed lower brain activation than HCs in bilateral dorsolateral prefrontal cortex and right frontal pole, these results were mainly driven by BDIIn patients. Moreover, subjective psychotic symptoms were positively significantly correlated with left dorsolateral prefrontal cortex activation in BDII patients. CONCLUSIONS Type II BD patients showed significant impairment when performing VFTs and reduced activation in the prefrontal cortex, and subjective psychotic symptoms were associated with brain activation in left dorsolateral prefrontal cortex in BDII patients.
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Affiliation(s)
- Gui-Fang Chen
- YuQuan Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Meng-Chai Mao
- Shanghai University of Traditional Chinese Medicine, Shanghai, China; Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation, Ministry of Education
| | - Kun Feng
- YuQuan Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Jie-Chun Gan
- YuQuan Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Xiao-Qian Zhang
- YuQuan Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Chen-Yu Shen
- YuQuan Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Bo Xu
- YuQuan Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Xiao-Min Liu
- Department of Neurology and Psychiatry, Beijing Shijitan Hospital, Capital Medical University, Beijing, China
| | - Xia-Jin Ren
- YuQuan Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Po-Zi Liu
- YuQuan Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China.
| | - Ya Wang
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, China.
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11
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Feng K, Law S, Ravindran N, Chen GF, Ma XY, Bo X, Zhang XQ, Shen CY, Li J, Wang Y, Liu XM, Sun JJ, Hu S, Liu PZ. Differentiating between bipolar and unipolar depression using prefrontal activation patterns: Promising results from functional near infrared spectroscopy (fNIRS) findings. J Affect Disord 2021; 281:476-484. [PMID: 33373907 DOI: 10.1016/j.jad.2020.12.048] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 12/08/2020] [Accepted: 12/11/2020] [Indexed: 01/10/2023]
Abstract
BACKGROUND Bipolar depression (BD) is a unique, severe and prevalent mental illness that shares many similarities in symptoms with unipolar depression (UD). Improving precision of their diagnoses would enhance treatment outcome and prognosis for both conditions. This study aims to provide evidence from functional Near-Infrared Spectroscopy (fNIRS) as a potential tool to differentiate UD and BD based on their differences in hemodynamic change in the prefrontal cortex during verbal fluency tasks (VFT). METHODS We enrolled 179 participants with clinically confirmed diagnoses, including 69 UD patients, 68 BD patients and 42 healthy controls(HC). Every participant was assessed using a 45-channel fNIRS and various clinical scales. FINDINGS Compared with HC, region-specific fNIR leads show UD patients had significant lower hemodynamic activation in 4 particular pre-frontal regions: 1) the left dorsolateral prefrontal cortex (DLPFC), 2) orbitofrontal cortex (OFC), 3) bilateral ventrolateral prefrontal cortex (VLPFC) and 4) left inferior frontal gyrus (IFG). In contrast, BD vs. HC comparisons showed only significant lower hemodynamic activation in the LIFG area. Furthermore, compared to BD patients, UD patients showed decreased hemodynamic activation changes in the VLPFC region. CONCLUSION Our results show significant frontal lobe activation pattern differences between UD and BD groups. fNIRS can be a potential tool to increase diagnostic precision for these conditions. In particular, the VLPFC area holds promise to be a useful site for such differentiation for further investigations.
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Affiliation(s)
- Kun Feng
- School of Clinical Medicine, Tsinghua University, Beijing, China; YuQuan Hospital, Tsinghua University, Beijing, 10000 China.
| | - Samuel Law
- Department of Psychiatry, University of Toronto, Canada
| | | | - Gui-Fang Chen
- School of Clinical Medicine, Tsinghua University, Beijing, China; YuQuan Hospital, Tsinghua University, Beijing, 10000 China
| | - Xiang-Yun Ma
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), National Clinical Research Center for Mental Disorders, Beijing, China
| | - Xu Bo
- YuQuan Hospital, Tsinghua University, Beijing, 10000 China
| | | | - Chen-Yu Shen
- YuQuan Hospital, Tsinghua University, Beijing, 10000 China
| | - Juan Li
- School of Clinical Medicine, Tsinghua University, Beijing, China; YuQuan Hospital, Tsinghua University, Beijing, 10000 China
| | - Ye Wang
- Department of Psychiatry, University of Toronto, Canada
| | - Xiao-Min Liu
- Department of Neurology and Psychiatry, Beijing Shijitan Hospital, Capital Medical University, Beijing, China
| | | | - Shuang Hu
- School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Po-Zi Liu
- School of Clinical Medicine, Tsinghua University, Beijing, China; YuQuan Hospital, Tsinghua University, Beijing, 10000 China.
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12
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Galeski S, Zhao X, Wawrzyńczak R, Meng T, Förster T, Lozano PM, Honnali S, Lamba N, Ehmcke T, Markou A, Li Q, Gu G, Zhu W, Wosnitza J, Felser C, Chen GF, Gooth J. Unconventional Hall response in the quantum limit of HfTe 5. Nat Commun 2020; 11:5926. [PMID: 33230118 PMCID: PMC7683529 DOI: 10.1038/s41467-020-19773-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 10/21/2020] [Indexed: 11/18/2022] Open
Abstract
Interacting electrons confined to their lowest Landau level in a high magnetic field can form a variety of correlated states, some of which manifest themselves in a Hall effect. Although such states have been predicted to occur in three-dimensional semimetals, a corresponding Hall response has not yet been experimentally observed. Here, we report the observation of an unconventional Hall response in the quantum limit of the bulk semimetal HfTe5, adjacent to the three-dimensional quantum Hall effect of a single electron band at low magnetic fields. The additional plateau-like feature in the Hall conductivity of the lowest Landau level is accompanied by a Shubnikov-de Haas minimum in the longitudinal electrical resistivity and its magnitude relates as 3/5 to the height of the last plateau of the three-dimensional quantum Hall effect. Our findings are consistent with strong electron-electron interactions, stabilizing an unconventional variant of the Hall effect in a three-dimensional material in the quantum limit.
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Affiliation(s)
- S Galeski
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany.
| | - X Zhao
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, 100190, Beijing, China
- Songshan Lake Materials Laboratory, 523808, Dongguan, Guangdong, China
- School of Physics Science, University of Chinese Academy of Sciences, 100049, Beijing, China
| | - R Wawrzyńczak
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - T Meng
- Institute of Theoretical Physics and Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, 01062, Dresden, Germany
| | - T Förster
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
| | - P M Lozano
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, 11794-3800, USA
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - S Honnali
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - N Lamba
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - T Ehmcke
- Institute of Theoretical Physics and Würzburg-Dresden Cluster of Excellence ct.qmat, Technische Universität Dresden, 01062, Dresden, Germany
| | - A Markou
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - Q Li
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY, 11794-3800, USA
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - G Gu
- Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, NY, USA
| | - W Zhu
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, 100190, Beijing, China
- School of Physics Science, University of Chinese Academy of Sciences, 100049, Beijing, China
| | - J Wosnitza
- Hochfeld-Magnetlabor Dresden (HLD-EMFL) and Würzburg-Dresden Cluster of Excellence ct.qmat, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany
| | - C Felser
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany
| | - G F Chen
- Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, 100190, Beijing, China
- Songshan Lake Materials Laboratory, 523808, Dongguan, Guangdong, China
- School of Physics Science, University of Chinese Academy of Sciences, 100049, Beijing, China
| | - J Gooth
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany.
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany.
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13
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Sirica N, Tobey RI, Zhao LX, Chen GF, Xu B, Yang R, Shen B, Yarotski DA, Bowlan P, Trugman SA, Zhu JX, Dai YM, Azad AK, Ni N, Qiu XG, Taylor AJ, Prasankumar RP. Tracking Ultrafast Photocurrents in the Weyl Semimetal TaAs Using THz Emission Spectroscopy. Phys Rev Lett 2019; 122:197401. [PMID: 31144919 DOI: 10.1103/physrevlett.122.197401] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 02/05/2019] [Indexed: 06/09/2023]
Abstract
We investigate polarization-dependent ultrafast photocurrents in the Weyl semimetal TaAs using terahertz (THz) emission spectroscopy. Our results reveal that highly directional, transient photocurrents are generated along the noncentrosymmetric c axis regardless of incident light polarization, while helicity-dependent photocurrents are excited within the ab plane. This is consistent with earlier static photocurrent experiments, and demonstrates on the basis of both the physical constraints imposed by symmetry and the temporal dynamics intrinsic to current generation and decay that optically induced photocurrents in TaAs are inherent to the underlying crystal symmetry of the transition metal monopnictide family of Weyl semimetals.
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Affiliation(s)
- N Sirica
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - R I Tobey
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
- Zernike Institute for Advanced Materials, University of Groningen, Groningen 9747AG, Netherlands
| | - L X Zhao
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - G F Chen
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - B Xu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - R Yang
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - B Shen
- Department of Physics and Astronomy and California NanoSystems Institute, University of California Los Angeles, Los Angeles, California 90095, USA
| | - D A Yarotski
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - P Bowlan
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - S A Trugman
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - J-X Zhu
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Y M Dai
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
- School of Physics, Nanjing University, Nanjing 210093, China
| | - A K Azad
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - N Ni
- Department of Physics and Astronomy and California NanoSystems Institute, University of California Los Angeles, Los Angeles, California 90095, USA
| | - X G Qiu
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - A J Taylor
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - R P Prasankumar
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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14
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Feng K, Shen CY, Ma XY, Chen GF, Zhang ML, Xu B, Liu XM, Sun JJ, Zhang XQ, Liu PZ, Ju Y. Effects of music therapy on major depressive disorder: A study of prefrontal hemodynamic functions using fNIRS. Psychiatry Res 2019; 275:86-93. [PMID: 30884335 DOI: 10.1016/j.psychres.2019.03.015] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 03/08/2019] [Accepted: 03/09/2019] [Indexed: 12/28/2022]
Abstract
Major depressive disorder (MDD) is a recurrent, chronic mental illness. While music therapy has been established as an effective treatment for MDD patients, the effects of this therapy on brain function remain unclear. This research employed near-infrared spectroscopy (NIRS) to explore the effects of music therapy on brain activity in mild or moderate MDD patients and to illustrate the potential mechanism of music therapy. Methods: Fifteen MDD patients and fifteen healthy controls (HC) underwent neuropsychological evaluations and NIRS measurements. All participants were treated with continuous music therapy for 10 days. Subsequently, all individuals were evaluated with neuropsychological assessments and NIRS measurements again. Results: The verbal fluency task (VFT) performances of the participants yielded significantly higher scores after music therapy in terms of vegetables, four-footed animals and fruit blocks. After the music treatment, the NIRS data showed that the mean active oxy-Hb values of channels 21, 23, 19, and 41 were significantly increased in both the MDD and HC groups. The MDD group showed significant activation in the dorsolateral prefrontal cortex (DLPFC), orbitofrontal cortex (OFC) and ventromedial prefrontal cortex (VMPFC) after music therapy. The results indicate that music therapy could improve the brain function of MDD patients.
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Affiliation(s)
- Kun Feng
- School of Clinical Medicine, Tsinghua University, Beijing, China; YuQuan Hospital, Tsinghua University, Beijing, 10000 China
| | - Chen-Yu Shen
- YuQuan Hospital, Tsinghua University, Beijing, 10000 China
| | - Xiang-Yun Ma
- Peking University Sixth Hospital, Peking University Institute of Mental Health, Key Laboratory of Mental Health, Ministry of Health (Peking University), National Clinical Research Center for Mental Disorders, Beijing, China
| | - Gui-Fang Chen
- School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Ming-Lu Zhang
- Bruce Copen Laboratories (Since 1947) GmbH & Co. KG Meisenweg 19a 82152 Krailling, Germany
| | - Bo Xu
- YuQuan Hospital, Tsinghua University, Beijing, 10000 China
| | - Xiao-Min Liu
- YuQuan Hospital, Tsinghua University, Beijing, 10000 China
| | - Jing-Jing Sun
- YuQuan Hospital, Tsinghua University, Beijing, 10000 China; Shanxi Medical University, Taiyuan, China
| | - Xiao-Qian Zhang
- School of Clinical Medicine, Tsinghua University, Beijing, China; YuQuan Hospital, Tsinghua University, Beijing, 10000 China
| | - Po-Zi Liu
- YuQuan Hospital, Tsinghua University, Beijing, 10000 China.
| | - Ya Ju
- Bruce Copen Laboratories (Since 1947) GmbH & Co. KG Meisenweg 19a 82152 Krailling, Germany.
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15
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Sun YM, Zhou JL, Wang L, Wu XN, Chen YP, Piao HX, Lu LG, Jiang W, Xu YQ, Feng B, Nan YM, Xie W, Chen GF, Zheng HW, Li H, Ding HG, Liu H, Lyu FD, Shao C, Wang TL, Ou XJ, Wang BQ, Chen SY, You H, Jia JD. [Qualitative pathological assessment of liver fibrosis regression after antiviral therapy in patients with chronic hepatitis B]. Zhonghua Gan Zang Bing Za Zhi 2019; 25:819-826. [PMID: 29325275 DOI: 10.3760/cma.j.issn.1007-3418.2017.11.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the methods for qualitative pathological assessment of dynamic changes in liver fibrosis/cirrhosis after antiviral therapy in patients with chronic hepatitis B (CHB), since antiviral therapy can partially reverse liver fibrosis and cirrhosis caused by hepatitis B and semi-quantitative, rather than qualitative, pathological assessment is often used for the research on liver fibrosis regression. Methods: Previously untreated CHB patients with liver fibrosis and cirrhosis were enrolled, and liver biopsy was performed before treatment and at 78 weeks after the antiviral therapy based on entecavir. The follow-up assessment was performed once every half a year. Based on the proportion of different types of fibrous septum, we put forward the new qualitative criteria called P-I-R classification (predominantly progressive, predominantly regressive, and indeterminate) for evaluating dynamic changes in liver fibrosis. This classification or Ishak fibrosis stage was used to evaluate the change in liver fibrosis after treatment and Ishak liver inflammation score was used to evaluate the change in liver inflammation after treatment. Results: A total of 112 CHB patients who underwent liver biopsy before and after treatment were enrolled, and among these patients, 71 with an Ishak stage of ≥3 and qualified results of live biopsy were included in the final analysis. Based on the P-I-R classification, 58% (41/71) were classified as predominantly progressive, 29% (21/71) were classified as indeterminate, and 13% (9/71) were classified as predominantly regressive; there were no significant differences between the three groups in alanine aminotransferase, aspartate aminotransferase, albumin, HBeAg positive rate, HBV DNA, and liver stiffness (P < 0.05). After treatment, the proportion of predominantly progressive, indeterminate, or predominantly regressive patients changed to 11% (8/71), 11% (8/71), and 78% (55/71), respectively. Among the 35 patients who had no change in Ishak stage after treatment, 72% (25/35) were classified as predominantly regressive and had certain reductions in the Laennec score, percentage of collagen area, and liver stiffness. Conclusion: This new P-I-R classification can be used to assess the dynamic changes in liver fibrosis after antiviral therapy in CHB patients.
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Affiliation(s)
- Y M Sun
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - J L Zhou
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - L Wang
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - X N Wu
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - Y P Chen
- Department of Infectious Diseases, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
| | - H X Piao
- Infectious Department, Affiliated Hospital of Yanbian University, Yanji 133000, China
| | - L G Lu
- Department of Gastroenterology and Hepatology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China
| | - W Jiang
- Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | - Y Q Xu
- Department of Digestive System, Beijing Tiantan Hospital, Capital Medical University, Beijing 100050, China
| | - B Feng
- Hepatology Institute, Peking University People's Hospital, Beijing 100044, China
| | - Y M Nan
- Department of Traditional and Western Medical Hepatology, Third Hospital of Hebei Medical University, Shijiazhuang 050051, China
| | - W Xie
- Center of Liver Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China
| | - G F Chen
- Second Liver Cirrhosis Diagnosis and Treatment Center, 302 Military Hospital of China, Beijing 100039, China
| | - H W Zheng
- Department of Infectious Disease, the Fifth Hospital of Shijiazhuang City, Shijiazhuang 050024, China
| | - H Li
- Department of Hepatopancreatobiliary and Splenic Medicine, Affiliated Hospital, Logistics University of People's Armed Police Force, Tianjin 300161, China
| | - H G Ding
- Department of Gastroenterology and Hepatology, Beijing Youan Hospital, Capital Medical University, Beijing 100069, China
| | - H Liu
- Department of Pathology, Beijing Youan Hospital, Capital Medical University, Beijing 100069, China
| | - F D Lyu
- Department of Pathology, Beijing Youan Hospital, Capital Medical University, Beijing 100069, China
| | - C Shao
- Department of Pathology, Beijing Youan Hospital, Capital Medical University, Beijing 100069, China
| | - T L Wang
- Department of Pathology, China-Japan Friendship Hospital, Beijing 100029, China
| | - X J Ou
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - B Q Wang
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - S Y Chen
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - H You
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
| | - J D Jia
- Liver Research Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China
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16
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Xu B, Zhao LX, Marsik P, Sheveleva E, Lyzwa F, Dai YM, Chen GF, Qiu XG, Bernhard C. Temperature-Driven Topological Phase Transition and Intermediate Dirac Semimetal Phase in ZrTe_{5}. Phys Rev Lett 2018; 121:187401. [PMID: 30444418 DOI: 10.1103/physrevlett.121.187401] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Indexed: 06/09/2023]
Abstract
We present an infrared spectroscopy study of ZrTe_{5}, which confirms a recent theoretical proposal that this material exhibits a temperature-driven topological quantum phase transition from a weak to a strong topological insulating state with an intermediate Dirac semimetal state around T_{p}≃138 K. Our study details the temperature evolution of the energy gap in the bulk electronic structure. We found that the energy gap closes around T_{p}, where the optical response exhibits characteristic signatures of a Dirac semimetal state, i.e., a linear frequency-dependent optical conductivity extrapolating to the origin (after subtracting a weak Drude response). This finding allows us to reconcile previous diverging reports about the topological nature of ZrTe_{5} in terms of a variation of T_{p} that depends on the crystal growth condition.
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Affiliation(s)
- B Xu
- Department of Physics and Fribourg Center for Nanomaterials, University of Fribourg, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
| | - L X Zhao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China
| | - P Marsik
- Department of Physics and Fribourg Center for Nanomaterials, University of Fribourg, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
| | - E Sheveleva
- Department of Physics and Fribourg Center for Nanomaterials, University of Fribourg, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
| | - F Lyzwa
- Department of Physics and Fribourg Center for Nanomaterials, University of Fribourg, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
| | - Y M Dai
- Center for Superconducting Physics and Materials, National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, China
| | - G F Chen
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China
| | - X G Qiu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China
| | - C Bernhard
- Department of Physics and Fribourg Center for Nanomaterials, University of Fribourg, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
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Chen GF, Liu LL, Cui JF, Chen T, Qin XJ, Gan JC, Bi B, Neumann DL, Shum DHK, Wang Y, Chan RCK. Life review therapy enhances mental time travel in patients with schizophrenia. Psychiatry Res 2017; 258:145-152. [PMID: 29024892 DOI: 10.1016/j.psychres.2017.10.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Revised: 10/01/2017] [Accepted: 10/01/2017] [Indexed: 01/07/2023]
Abstract
Mental Time Travel (MTT) is the ability of individuals to project themselves to the past or to the future. Studies have shown that schizophrenia (SZ) patients are impaired in MTT. The present study aimed to examine whether MTT in patients with SZ can be improved through Life Review Therapy. Fifty patients with SZ were randomly assigned to the training (SZ-training) or control (SZ-control) group. Whereas the SZ-training group received four-week Life Review Therapy in addition to conventional treatment, the SZ-control group only received conventional treatment. MTT, emotional status, life satisfaction and cognitive functions were assessed before and after the training. We also recruited 25 matched healthy controls to complete all the assessments at baseline. After training, the SZ-training group showed higher specificity and more field perspective than the SZ-control group. No significant difference was found between the SZ-training group post-training assessment and the healthy controls. The SZ-training group also showed significant improvements in emotional expression, semantic memory and verbal fluency, but the SZ-control group did not show such improvements. These results indicated that Life Review Therapy is effective in improving MTT of SZ patients.
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Affiliation(s)
- Gui-Fang Chen
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, China; The Second People's Hospital of Guizhou Province, Guiyang, China
| | - Lu-Lu Liu
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Ji-Fang Cui
- Information Center, National Institute of Education Sciences, Beijing, China
| | - Tao Chen
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Xiao-Jing Qin
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
| | - Jie-Chun Gan
- The Second People's Hospital of Guizhou Province, Guiyang, China
| | - Bin Bi
- The Second People's Hospital of Guizhou Province, Guiyang, China
| | - David L Neumann
- Menzies Health Institute Queensland and School of Applied Psychology, Griffith University, Gold Coast, Australia
| | - David H K Shum
- Menzies Health Institute Queensland and School of Applied Psychology, Griffith University, Gold Coast, Australia
| | - Ya Wang
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, China.
| | - Raymond C K Chan
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, CAS Key Laboratory of Mental Health, Institute of Psychology, Beijing, China; Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
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18
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Chen GF, Ping J, Gu HT, Zhao ZM, Zhou Y, Xing F, Tao YY, Mu YP, Liu P, Liu CH. [Correlation of liver stiffness measured by FibroTouch and FibroScan with Ishak fibrosis score in patients with chronic hepatitis B]. Zhonghua Gan Zang Bing Za Zhi 2017; 25:145-150. [PMID: 28297803 DOI: 10.3760/cma.j.issn.1007-3418.2017.02.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: To investigate the correlation of liver stiffness measured by FibroTouch (FT) and FibroScan (FS) with Ishak fibrosis score in patients with chronic hepatitis B. Methods: A total of 313 patients with chronic hepatitis B who visited Department of Liver Cirrhosis in Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine from November 2014 to May 2016 were enrolled. All the patients underwent liver biopsy, and FT and FS were used to determine liver stiffness measurement (LSM). Serum biochemical parameters were measured, and the aspartate aminotransferase-to-platelet ratio index (APRI) in a multi-parameter model of liver fibrosis and fibrosis-4 (FIB-4) index were calculated. The consistency between the results of four noninvasive examinations and Ishak fibrosis score was compared. The t-test was used for comparison of LSM determined by FT and FS. Pearson correlation analysis was used investigate the correlation between LSM determined by FT and FS; Spearman correlation analysis was used to investigate the correlation of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels and Knodell score with LSM determined by FT and FS; the correlation between LSM determined by FT and FS and fibrosis stage was analyzed by partial correlation analysis adjusted by Knodell score for liver inflammatory activity; Spearman correlation analysis was used for APRI, FIB-4, and fibrosis stage. Based on the Ishak fibrosis score, the receiver operating characteristic (ROC) curve was used to analyze the values of four noninvasive methods in the diagnosis of liver fibrosis. Results: There was no significant difference in LSM measured by FT and FS in all patients (15.75±9.42 kPa vs 15.42±10.52 kPa, P > 0.05) and Pearson correlation analysis indicated a significant positive correlation between them (r = 0.858, P < 0.01); serum ALT and AST levels and liver inflammatory activity were correlated with LSM determined by FT and FS. There was a significant positive correlation between LSM determined by FT and FS and fibrosis stage (r = 0.501 and 0.526, both P < 0.001), and APRI and FIB-4 were also positively correlated with fibrosis stage (r = 0.236 and 0.218, both P < 0.001). Based on the Ishak fibrosis score, in the diagnosis of fibrosis stages F3, F4, F5, and F6, the areas under the ROC curve were 0.915/0.856/0.839/0.816 for FT, 0.933/0.883/0.849/0.856 for FS, 0.618/0.630/0.608/0.638 for APRI, and 0.614/0.624/0.595/0.649 for FIB-4, and FT and FS had a significantly larger areas under the ROC curve than APRI and FIB-4. Conclusion: LSM determined by FT or FS has a good correlation with the Ishak fibrosis score, so FT and FS have a significantly better diagnostic performance for liver fibrosis than APRI and FIB-4.
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Affiliation(s)
- G F Chen
- Liver Cirrhosis Department, Shuguang Hospital affiliated to Shanghai University of Traditional Chinese Medicine, Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - J Ping
- Shanghai Key Laboratory of Traditional Chinese Clinical Medicine, Shanghai 201203, China
| | - H T Gu
- Liver Cirrhosis Department, Shuguang Hospital affiliated to Shanghai University of Traditional Chinese Medicine, Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Z M Zhao
- Shanghai Key Laboratory of Traditional Chinese Clinical Medicine, Shanghai 201203, China
| | - Y Zhou
- Liver Cirrhosis Department, Shuguang Hospital affiliated to Shanghai University of Traditional Chinese Medicine, Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - F Xing
- Liver Cirrhosis Department, Shuguang Hospital affiliated to Shanghai University of Traditional Chinese Medicine, Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Y Y Tao
- Liver Cirrhosis Department, Shuguang Hospital affiliated to Shanghai University of Traditional Chinese Medicine, Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - Y P Mu
- Liver Cirrhosis Department, Shuguang Hospital affiliated to Shanghai University of Traditional Chinese Medicine, Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - P Liu
- Liver Cirrhosis Department, Shuguang Hospital affiliated to Shanghai University of Traditional Chinese Medicine, Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
| | - C H Liu
- Liver Cirrhosis Department, Shuguang Hospital affiliated to Shanghai University of Traditional Chinese Medicine, Institute of Liver Diseases, Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
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19
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Mu YP, Zhang X, Fan WW, Li XW, Chen GF, Chen JM, Zhang H, Liu P. [Mechanism of Astragaloside prevents cholestatic liver fibrosis through inhibition of Notch signaling activation]. Zhonghua Gan Zang Bing Za Zhi 2017; 25:575-582. [PMID: 29056006 DOI: 10.3760/cma.j.issn.1007-3418.2017.08.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: The Notch signaling pathway is closely related to biliary fibrosis. Previous studies have shown that Astragaloside (AS) can prevent the progression of cholestatic liver fibrosis. The purpose of this study is to observe the effect of AS on the regulation of Notch signaling pathway in biliary fibrosis. Methods: Cholestatic liver fibrosis was established by common bile duct ligation (BDL) in rats. Two weeks after BDL, the rats were randomly divided into a model group (i.e., BDL), an Astragalosides group (AS), and a sorafenib (SORA) positive control group and treated for 3 weeks. Bile duct proliferation and liver fibrosis were determined by tissue staining. Protein and gene expression were determined by immunostaining, immunoblotting and RT-PCR, respectively. Activation of the Notch signaling pathway was evaluated by analyzing expressions of Notch-1, -2, -3, -4, Jagged (JAG)1, Delta like (DLL)-1, -3, -4, Hes1, Numb and RBP-Jκ. Statistical analysis of variance analysis, q test, P < 0.05 showed that the difference was statistically significant. Results: (1) AS significantly reduced the deposition of collagen and the Hyp content of liver tissue (500.15 ± 86.10 vs. 625.72 ± 105.62, P = 0.031), and inhibited the activation of hepatic stellate cells. (2) AS significantly decreased the protein and mRNA expressions of transforming growth factor (TGF)-β1 (1.02±0.15 vs. 1.89±0.36, P = 0.007; 1.17±0.18 vs. 1.68±0.29, P = 0.013, respectively) and α-smooth muscle actin (α-SMA, 0.41±0.11 vs. 0.72±0.16, P = 0.003; 1.71±0.57 vs. 2.68±0.46, P = 0.008, respectively) compared with BDL group. In contrast, AS significantly enhanced expression of the Smad 7 protein compared with the BDL group (0.72±0.008 vs. 0.33±0.001, P = 0.005). AS also reduced biliary epithelial cell proliferation. AS reduced the mRNA levels of CK7, CK8 and CK18 (1.31±0.39 vs. 2.63±0.82, P = 0.009; 0.71±0.09 vs. 0.87±0.08, P = 0.031; 2.56±0.32 vs. 3.41±0.39, P = 0.010, respectively) and reduced the positive areas of CK19 and OV6 (62 337.17±21 873.38 vs. 22 5472.67±26 933.63, P = 0.000; 92 237.43±15 894.11 vs. 171 298.13±61 761.37, P = 0.000, respectively). (3) The mRNA expression of Notch-2, -3, -4 and JAG1 were significantly reduced in the AS group compared to the BDL group (1.07±0.19 vs. 1.51±0.28, P = 0.044; 0.99±0.24 vs. 1.18±0.10, P = 0.043; 1.36±0.42 vs. 3.40±0.44, P = 0.048; 2.62±0.43 vs. 3.73±0.83, P = 0.046, respectively). In contrast, the mRNA level of Numb was clearly enhanced after AS treatment (0.90±0.05 vs. 0.75±0.11, P = 0.019). In addition, consistent with the mRNA levels, the protein expressions of Notch-2, -3, -4 and JAG1 were reduced significantly (1.27±0.18 vs. 1.71±0.26, P = 0.004; 0.99±0.11 vs. 4.38±0.60, P = 0.001; 1.76±0.32 vs. 4.01±0.74, P = 0.002; 1.62±0.33 vs. 2.74±0.63, P = 0.002) and the Numb protein level was increased significantly (1.50±0.15 vs. 0.85±0.11, P = 0.001) in AS group compared with BDL group. Conclusion: AS may prevent cholestatic liver fibrosis via inhibition of the Notch signaling pathway, thereby inhibiting the abnormal proliferation of biliary epithelial cells. Results indicate that AS may be a potential treatment for cholestatic liver disease.
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Affiliation(s)
- Y P Mu
- Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine; Institute of Liver Diseases, Shanghai University of Traditional Chinese Medicine, Shanghai 201203, China
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20
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Chen D, Zhang S, Yang HX, Li JQ, Chen GF. Magnetic and transport properties of a layered compound Ce 2Te 5. J Phys Condens Matter 2017; 29:265803. [PMID: 28440786 DOI: 10.1088/1361-648x/aa6f49] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Ce2Te5 single crystals were successfully grown using RbCl/LiCl flux method. The structure of Ce2Te5 can be viewed as a combination of CeTe2 and CeTe3. The experimental results of magnetic susceptibility [Formula: see text], isothermal magnetization M(H), electrical resistivity [Formula: see text], and heat capacity C(T) show two clear anomalies at 5.1 and 2.3 K, which correspond to a ferrimagnetic and a possible antiferromagnetic transition, respectively. Both of [Formula: see text] and C(T) confirm a third transition at 0.9 K. The resistivity shows a huge anisotropy with the current applied in [Formula: see text] and [Formula: see text] directions. Our experimental results prefer the scenario that the three consecutive transitions in Ce2Te5 are attributed to two different kinds of origin, which are independent and responsible for the magnetic orders observed in CeTe2 and CeTe3.
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Affiliation(s)
- D Chen
- Department of Physics, Renmin University of China, Beijing 100872, People's Republic of China. Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
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21
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Abstract
A novel, efficient, and facile protocol has been developed for transforming 2-hydroxybenzonitriles and bromides into a range of 3-aryl or alkyl substituted 1,2-benzisoxazoles in good to excellent yields mediated by PPh3. The electronic and steric effects of bromides on the reaction are discussed. This is the first example to construct a C-C bond and heterocycle in a Barbier-Grignard-type reaction featuring easier recovery of PPh3 than a metallic catalyst in one step.
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Affiliation(s)
- GuiFang Chen
- Department of Chemistry, College of Chemistry and Materials, Jinan University , Guangzhou 510632, China
| | - Hong Liu
- Department of Chemistry, College of Chemistry and Materials, Jinan University , Guangzhou 510632, China
| | - ShuJia Li
- Department of Chemistry, College of Chemistry and Materials, Jinan University , Guangzhou 510632, China
| | - Yu Tang
- Department of Chemistry, College of Chemistry and Materials, Jinan University , Guangzhou 510632, China
| | - PeiYao Lu
- Department of Pharmacy, College of Pharmacy, Jinan University , Guangzhou 510632, China
| | - KaiTian Xu
- Department of Chemistry, College of Chemistry and Materials, Jinan University , Guangzhou 510632, China
| | - YuanMing Zhang
- Department of Chemistry, College of Chemistry and Materials, Jinan University , Guangzhou 510632, China
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22
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Xu B, Dai YM, Zhao LX, Wang K, Yang R, Zhang W, Liu JY, Xiao H, Chen GF, Trugman SA, Zhu JX, Taylor AJ, Yarotski DA, Prasankumar RP, Qiu XG. Temperature-tunable Fano resonance induced by strong coupling between Weyl fermions and phonons in TaAs. Nat Commun 2017; 8:14933. [PMID: 28358027 PMCID: PMC5379101 DOI: 10.1038/ncomms14933] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 02/09/2017] [Indexed: 11/30/2022] Open
Abstract
Strong coupling between discrete phonon and continuous electron–hole pair excitations can induce a pronounced asymmetry in the phonon line shape, known as the Fano resonance. This effect has been observed in various systems. Here we reveal explicit evidence for strong coupling between an infrared-active phonon and electronic transitions near the Weyl points through the observation of a Fano resonance in the Weyl semimetal TaAs. The resulting asymmetry in the phonon line shape, conspicuous at low temperatures, diminishes continuously with increasing temperature. This behaviour originates from the suppression of electronic transitions near the Weyl points due to the decreasing occupation of electronic states below the Fermi level (EF) with increasing temperature, as well as Pauli blocking caused by thermally excited electrons above EF. Our findings not only elucidate the mechanism governing the tunable Fano resonance but also open a route for exploring exotic physical phenomena through phonon properties in Weyl semimetals. The study of lattice vibrations coupled to electronic excitations may provide an avenue for exploring exotic physical phenomena. Here, Xu et al. observe a Fano resonance in the Weyl semimetal TaAs, revealing evidence for a strong coupling between phonons and Weyl fermions.
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Affiliation(s)
- B Xu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China.,Center for High Pressure Science and Technology Advanced Research, Beijing 100094, China
| | - Y M Dai
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - L X Zhao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China
| | - K Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China
| | - R Yang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China
| | - W Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China
| | - J Y Liu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China
| | - H Xiao
- Center for High Pressure Science and Technology Advanced Research, Beijing 100094, China
| | - G F Chen
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China.,Collaborative Innovation Center of Quantum Matter, Beijing 100190, China
| | - S A Trugman
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.,Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - J-X Zhu
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.,Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - A J Taylor
- Associate Directorate for Chemistry, Life and Earth Sciences, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - D A Yarotski
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - R P Prasankumar
- Center for Integrated Nanotechnologies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - X G Qiu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190, China.,Collaborative Innovation Center of Quantum Matter, Beijing 100190, China
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Liu Y, Long YJ, Zhao LX, Nie SM, Zhang SJ, Weng YX, Jin ML, Li WM, Liu QQ, Long YW, Yu RC, Gu CZ, Sun F, Yang WG, Mao HK, Feng XL, Li Q, Zheng WT, Weng HM, Dai X, Fang Z, Chen GF, Jin CQ. Superconductivity in HfTe 5 across weak to strong topological insulator transition induced via pressures. Sci Rep 2017; 7:44367. [PMID: 28300156 PMCID: PMC5353664 DOI: 10.1038/srep44367] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 02/07/2017] [Indexed: 11/17/2022] Open
Abstract
Recently, theoretical studies show that layered HfTe5 is at the boundary of weak & strong topological insulator (TI) and might crossover to a Dirac semimetal state by changing lattice parameters. The topological properties of 3D stacked HfTe5 are expected hence to be sensitive to pressures tuning. Here, we report pressure induced phase evolution in both electronic & crystal structures for HfTe5 with a culmination of pressure induced superconductivity. Our experiments indicated that the temperature for anomaly resistance peak (Tp) due to Lifshitz transition decreases first before climbs up to a maximum with pressure while the Tp minimum corresponds to the transition from a weak TI to strong TI. The HfTe5 crystal becomes superconductive above ~5.5 GPa where the Tp reaches maximum. The highest superconducting transition temperature (Tc) around 5 K was achieved at 20 GPa. Crystal structure studies indicate that HfTe5 transforms from a Cmcm phase across a monoclinic C2/m phase then to a P-1 phase with increasing pressure. Based on transport, structure studies a comprehensive phase diagram of HfTe5 is constructed as function of pressure. The work provides valuable experimental insights into the evolution on how to proceed from a weak TI precursor across a strong TI to superconductors.
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Affiliation(s)
- Y Liu
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - Y J Long
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - L X Zhao
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - S M Nie
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - S J Zhang
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - Y X Weng
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - M L Jin
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - W M Li
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - Q Q Liu
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - Y W Long
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - R C Yu
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - C Z Gu
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - F Sun
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China
| | - W G Yang
- Center for High Pressure Science &Technology Advanced Research, Shanghai, 201203, China
| | - H K Mao
- Center for High Pressure Science &Technology Advanced Research, Shanghai, 201203, China
| | - X L Feng
- Department of Materials Science, Jilin University, Changchun 130012, China
| | - Q Li
- Department of Materials Science, Jilin University, Changchun 130012, China
| | - W T Zheng
- Department of Materials Science, Jilin University, Changchun 130012, China
| | - H M Weng
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.,Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - X Dai
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.,Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - Z Fang
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.,Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - G F Chen
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.,Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - C Q Jin
- Institute of Physics &School of Physics of University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100190, China.,Collaborative Innovation Center of Quantum Matter, Beijing, China
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24
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Wu F, Wu LL, Chen GF, Huang YC. [Retrospective study on the efficacy of different chemotherapy regimens concurrently combined with intensity modulated radiation therapyin treatment of Ⅲ-Ⅳa stage nasopharyngeal carcinoma]. Lin Chuang Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2016; 30:1536-1539. [PMID: 29871135 DOI: 10.13201/j.issn.1001-1781.2016.19.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Indexed: 06/08/2023]
Abstract
Objective:To compare the near and long term efficacy and safety of paclitaxel(TAX) plus cisplatin(DDP) (TP regimen) and DDP plus 5-FU(PF regimen) concurrently combined with IMRT in treatment of patients with advanced NPC.Method: A retrospective analysis on 108 advanced NPC cases from January 2010 to December 2012 was conducted. The patients were divided into TP group(57 cases) and PF group(51 cases) according to therapy regimen. TP group received IMRT combined with TP therapy, and PF group received IMRT combined with PF regimen, two groups were both used 4 cycles of chemotherapy, toxicity reactions during concurrent radiochemotherapy were noted. Two months after treatment, near clinical efficacies of the two groups were determined, and then, a three years followingup was conducted, during which recurrence ratio, metastasis ratio, local control ratio and survival rate were analyzed. Result: Two months after treatment, the total effective ratio of TP group(84.2% vs.76.5%) was higher than PF group,however, the difference was not statistically significant(P>0.05). Gastrointestinal reaction(70.2% vs.66.7%), marrow inhibition(75.4% vs.82.4%), liver function damage(12.3% vs.13.7%), radioactive oral and pharyngeal injury(91.2% vs.98.0%), hearing damage(15.8% vs.15.7%) in the two groups during chemoradiotherapy had no significant differences(P>0.05). During followingup, the recurrence and metastasis ratio in TP group(33.3% vs.47.1%) was lower than PF group(χ²=2.116,P=0.146). TP group with The local control rate(73.7% vs.68.5%) and survival rate(84.2% vs.78.4%) after three years treatment in TP group were higher than PF group(χ²=0.336,P=0.562;χ²=0.596,P=0.440). Conclusion: IMRT concurrently combined with TP and PF respectively are both effective methods for treatment of advanced NPC. In this study, IMPT plus TP concurrent chemoradiotherapy has a certain superiority in near and long term clinical treatment efficacy and safety.
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Affiliation(s)
- F Wu
- Department of Otolaryngology,the Second Hospital Affiliated to Hubei University of Science and Technology,Xianning,437100,China
| | - L L Wu
- Department of Otolaryngology,the Second Hospital Affiliated to Hubei University of Science and Technology,Xianning,437100,China
| | - G F Chen
- Department of Medical Institute of Technology, Taizhou Polytechnic College
| | - Y C Huang
- Five senses Medical College,Hubei Science and Technology College
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25
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Lv BQ, Muff S, Qian T, Song ZD, Nie SM, Xu N, Richard P, Matt CE, Plumb NC, Zhao LX, Chen GF, Fang Z, Dai X, Dil JH, Mesot J, Shi M, Weng HM, Ding H. Observation of Fermi-Arc Spin Texture in TaAs. Phys Rev Lett 2015; 115:217601. [PMID: 26636872 DOI: 10.1103/physrevlett.115.217601] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Indexed: 06/05/2023]
Abstract
We have investigated the spin texture of surface Fermi arcs in the recently discovered Weyl semimetal TaAs using spin- and angle-resolved photoemission spectroscopy. The experimental results demonstrate that the Fermi arcs are spin polarized. The measured spin texture fulfills the requirement of mirror and time-reversal symmetries and is well reproduced by our first-principles calculations, which gives strong evidence for the topologically nontrivial Weyl semimetal state in TaAs. The consistency between the experimental and calculated results further confirms the distribution of chirality of the Weyl nodes determined by first-principles calculations.
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Affiliation(s)
- B Q Lv
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - S Muff
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - T Qian
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Z D Song
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - S M Nie
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - N Xu
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - P Richard
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - C E Matt
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - N C Plumb
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - L X Zhao
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - G F Chen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - Z Fang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - X Dai
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - J H Dil
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - J Mesot
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
- Laboratory for Solid State Physics, ETH Zürich, CH-8093 Zürich, Switzerland
| | - M Shi
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - H M Weng
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - H Ding
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing, China
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26
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Ma X, Xue M, Li F, Chen J, Chen D, Wang X, Pan F, Chen GF. Gradual-order enhanced stability: a frozen section of electrospun nanofibers for energy storage. Nanoscale 2015; 7:8715-8719. [PMID: 25916943 DOI: 10.1039/c5nr01502b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A combination of electrospinning and a frozen section has been used to gradually lower the scale of the active materials, thus effectively avoiding nano-reunion, to a certain extent, during electrode fabrication. The as-fabricated electrode-based supercapacitor possesses high electrochemical capacitance and good stability. Our results demonstrate a universal top-down route for the controllable fabrication of homodisperse nanoparticle electrodes for use in high performance electrochemical devices.
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Affiliation(s)
- Xinlei Ma
- Research Center for Bioengineering and Sensing Technology, University of Science & Technology Beijing, Beijing, P. R. China
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27
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Chen GF, Shi TP, Wang BJ, Wang XY, Zang Q. EFFICACY OF DIFFERENT RESECTIONS ON NON-MUSCLE-INVASIVE BLADDER CANCER AND ANALYSIS OF THE OPTIMAL SURGICAL METHOD. J BIOL REG HOMEOS AG 2015; 29:465-470. [PMID: 26122238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This study aimed to analyze the clinical efficacy of different resections in treating non-muscle-invasive bladder cancer (NMIBC), including partial cystectomy, transurethral resection of bladder tumor (TURBT) and holmium laser resection of bladder tumor. Two hundred and sixteen patients were recruited with NMIBC who were available for follow-up visits in hospital, including 62 cases treated with partial cystectomy, 90 cases treated with TURBT and 64 cases with holmium laser resection. Analysis was made on the cases with tumor relapse in the two years, on operation time, blood loss, time for indwelling urinary catheter, hospital stay and complications after operation. Results were compared to the clinical efficacy of these operation patterns. It was found that the two-year relapse rate for TURBT group, partial cystectomy group and Holmium laser resection group was 41%, 31%, and 33% respectively, and the difference had no statistical significance (p>0.05). Both the TURBT group and holmium laser resection group had shorter operation time, hospital stay and time for indwelling urinary catheter as well as much less blood loss when compared with the partial cystectomy group; the difference had statistical significance (p<0.001). In terms of complications, the TURBT group was likely to induce obturator nerve reflex and bladder perforation while the partial cystectomy group was likely to induce bladder spasm. Therefore, this study presumes that holmium laser resection and TURBT are much safer and quicker for recovery and obviously superior to the partial cystectomy.
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Affiliation(s)
- G F Chen
- Department of Urology, the General Hospital of the Chinese Peoples Liberation Army, Haidian, Beijing, China
| | - T P Shi
- Department of Urology, the General Hospital of the Chinese Peoples Liberation Army, Haidian, Beijing, China
| | - B J Wang
- Department of Urology, the General Hospital of the Chinese Peoples Liberation Army, Haidian, Beijing, China
| | - X Y Wang
- Department of Urology, the General Hospital of the Chinese Peoples Liberation Army, Haidian, Beijing, China
| | - Q Zang
- Department of Urology, the General Hospital of the Chinese Peoples Liberation Army, Haidian, Beijing, China
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28
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Abstract
This article aimed to investigate the value of α-fetoprotein (AFP) for the diagnosis of hepatocellular carcinoma (HCC) and to evaluate the relationship between AFP and various clinical variables of HCC comprehensively. A retrospective study of postoperative patients diagnosed with liver neoplasm from two Chinese centers was enrolled in our study.A total of 3050 patients were included. The best cut-off point of AFP for the diagnosis of HCC was 20ng/ml with ideal sensitivity (69.74%), specificity (91.18%), LR (4.12) and YI (0.61). Non-HBV infection patients showed the highest specificity (94.44%) but lowest sensitivity (60.13%). In HBV infection. Patients, HBsAg, HBeAb, and HBcAb positive patients had the highest sensitivity (79.55%) and specificity (58.49%). AFP levels increased significantly in symptomatic patients (p=0.011). Those patients with tumor sizes ≥10cm had much higher serum AFP level compared with smaller tumors ones (p=0.014). AFP levels increased remarkably in patients with vascular invasion (p=0.015). Stepwise logistic regression showed tumor size (≥10cm) was an independent predictor of elevated AFP (OR=2.743, 95%CI: 1.167-6.447, P=0.021). The best discriminating AFP value for the diagnosis of HCC is 20ng/ml; HBsAg, HBeAb and HBcAb positive patients have the optimal sensitivity and specificity; tumor size ≥ 10cm is an independent predictor of elevated AFP.
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29
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Zhu GY, Chen GF, Li JT, Shi ZL, Lin Y, Ding T, Xu XY, Dai J, Xu CX. Fabrication and characterization of n-ZnO nanonails array/p(+)-GaN heterojunction diode. J Nanosci Nanotechnol 2012; 12:7950-7953. [PMID: 23421162 DOI: 10.1166/jnn.2012.6658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A novel heterojunctional structure of n-ZnO nanonails array/p(+)-GaN light-emitting diode was fabricated by Chemical Vapor Deposition method. A broad electroluminescence spectrum shows two peaks centered at 435 nm and 478 nm at room temperature, respectively. By comparing the photoluminescence and electroluminescence spectra, together with analyzing the energy band structure of heterojunction light emitting diode, it suggested that the electroluminescence peak located at 435 nm originates from Mg acceptor level of p(+)-GaN layer, whereas the electroluminescence peak located at 478 nm originates from the defects of n-ZnO nanonails array.
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Affiliation(s)
- G Y Zhu
- State Key Laboratory of Bioelectronics, School of Electronic Science and Engineering, Southeast University, Nanjing 210096, China
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30
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Wang NL, Hu WZ, Chen ZG, Yuan RH, Li G, Chen GF, Xiang T. High energy pseudogap and its evolution with doping in Fe-based superconductors as revealed by optical spectroscopy. J Phys Condens Matter 2012; 24:294202. [PMID: 22773312 DOI: 10.1088/0953-8984/24/29/294202] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We report optical spectroscopic measurements on electron- and hole-doped BaFe2As2. We show that the compounds in the normal state are not simple metals. The optical conductivity spectra contain, in addition to the free carrier response at low frequency, a temperature-dependent gap-like suppression at fairly high energy scale near 0.6 eV. This suppression evolves with the As–Fe–As bond angle induced by electron or hole doping. Furthermore, the feature becomes much weaker in the Fe-chalcogenide compounds. We elaborate that the feature is mainly caused by the strong Hund's rule coupling effect between the itinerant electrons and localized electron moment arising from the multiple Fe 3d orbitals. The coupling strength changes with the environment of the Fe atom. Our experiments demonstrate the coexistence of itinerant and localized electrons in iron-based compounds, which would then lead to a more comprehensive picture of the metallic magnetism in the materials.
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Affiliation(s)
- N L Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy ofSciences, Beijing 100190, People’s Republic of China
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31
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Xue M, Cao T, Wang D, Wu Y, Yang H, Dong X, He J, Li F, Chen GF. Superconductivity above 30 K in alkali-metal-doped hydrocarbon. Sci Rep 2012; 2:389. [PMID: 22548129 PMCID: PMC3339435 DOI: 10.1038/srep00389] [Citation(s) in RCA: 137] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Accepted: 03/26/2012] [Indexed: 11/09/2022] Open
Abstract
The recent discovery of superconductivity with a transition temperature (T(c)) at 18 K in K(x)picene has extended the possibility of high-T(c) superconductors in organic materials. Previous experience based on similar hydrocarbons, like alkali-metal doped phenanthrene, suggested that even higher transition temperatures might be achieved in alkali-metals or alkali-earth-metals doped such polycyclic-aromatic-hydrocarbons (PAHs), a large family of molecules composed of fused benzene rings. Here we report the discovery of high-T(c) superconductivity at 33 K in K-doped 1,2:8,9-dibenzopentacene (C(30)H(18)). To our best knowledge, it is higher than any T(c) reported previously for an organic superconductor under ambient pressure. This finding provides an indication that superconductivity at much higher temperature may be possible in such PAHs system and is worthy of further exploration.
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32
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Oka T, Li Z, Kawasaki S, Chen GF, Wang NL, Zheng GQ. Antiferromagnetic spin fluctuations above the dome-shaped and full-gap superconducting states of LaFeAsO1-xFx revealed by (75)As-nuclear quadrupole resonance. Phys Rev Lett 2012; 108:047001. [PMID: 22400880 DOI: 10.1103/physrevlett.108.047001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Revised: 07/09/2011] [Indexed: 05/31/2023]
Abstract
We report a systematic study by (75)As nuclear-quadrupole resonance in LaFeAsO(1-x)F(x). The antiferromagnetic spin fluctuation found above the magnetic ordering temperature T(N) = 58 K for x = 0.03 persists in the regime 0.04 ≤ x ≤ 0.08, where superconductivity sets in. A dome-shaped x dependence of the superconducting transition temperature T(c) is found, with the highest T(c) = 27 K at x = 0.06, which is realized under significant antiferromagnetic spin fluctuation. With increasing x further, the antiferromagnetic spin fluctuation decreases, and so does T(c). These features resemble closely the cuprates La(2-x)Sr(x)CuO(4). In x = 0.06, the spin-lattice relaxation rate (1/T(1)) below T(c) decreases exponentially down to 0.13T(c), which unambiguously indicates that the energy gaps are fully opened. The temperature variation of 1/T(1) below T(c) is rendered nonexponential for other x by impurity scattering.
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Affiliation(s)
- T Oka
- Department of Physics, Okayama University, Okayama 700-8530, Japan
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33
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Umezawa K, Li Y, Miao H, Nakayama K, Liu ZH, Richard P, Sato T, He JB, Wang DM, Chen GF, Ding H, Takahashi T, Wang SC. Unconventional anisotropic s-wave superconducting gaps of the LiFeAs iron-pnictide superconductor. Phys Rev Lett 2012; 108:037002. [PMID: 22400776 DOI: 10.1103/physrevlett.108.037002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Indexed: 05/31/2023]
Abstract
We have performed high-resolution angle-resolved photoemission spectroscopy on Fe-based superconductor LiFeAs (T(c)=18 K). We reveal multiple nodeless superconducting (SC) gaps with 2Δ/k(B)T(c) ratios varying from 2.8 to 6.4, depending on the Fermi surface (FS). We also succeeded in directly observing a gap anisotropy along the FS with magnitude up to ~30%. The anisotropy is fourfold symmetric with an antiphase between the hole and electron FSs, suggesting complex anisotropic interactions for the SC pairing. The observed momentum dependence of the SC gap offers an excellent opportunity to investigate the underlying pairing mechanism.
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Affiliation(s)
- K Umezawa
- Department of Physics, Tohoku University, Sendai 980-8578, Japan
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Yu W, Ma L, He JB, Wang DM, Xia TL, Chen GF, Bao W. 77Se NMR study of the pairing symmetry and the spin dynamics in K(y)Fe(2-x)Se2. Phys Rev Lett 2011; 106:197001. [PMID: 21668191 DOI: 10.1103/physrevlett.106.197001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Indexed: 05/30/2023]
Abstract
We present a 77Se NMR study of the newly discovered iron selenide superconductor K(y)Fe(2-x)Se2, in which T(c) = 32 K. Below T(c), the Knight shift 77K drops sharply with temperature, providing strong evidence for singlet pairing. Above T(c), Korringa-type relaxation indicates Fermi-liquid behavior. Our experimental results set strict constraints on the nature of possible theories for the mechanism of high-T(c) superconductivity in this iron selenide system.
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Affiliation(s)
- Weiqiang Yu
- Department of Physics, Renmin University of China, Beijing 100872, China.
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Ding H, Nakayama K, Richard P, Souma S, Sato T, Takahashi T, Neupane M, Xu YM, Pan ZH, Fedorov AV, Wang Z, Dai X, Fang Z, Chen GF, Luo JL, Wang NL. Electronic structure of optimally doped pnictide Ba0.6K0.4Fe2As2: a comprehensive angle-resolved photoemission spectroscopy investigation. J Phys Condens Matter 2011; 23:135701. [PMID: 21415479 DOI: 10.1088/0953-8984/23/13/135701] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The electronic structure of the Fe-based superconductor Ba(0.6)K(0.4)Fe(2)As(2) is studied by means of angle-resolved photoemission. We identify dispersive bands crossing the Fermi level forming hole-like (electron-like) Fermi surfaces (FSs) around Γ (M) with nearly nested FS pockets connected by the antiferromagnetic wavevector. Compared to band structure calculation findings, the overall bandwidth is reduced by a factor of 2 and the low energy dispersions display even stronger mass renormalization. Using an effective tight banding model, we fitted the band structure and the FSs to obtain band parameters reliable for theoretical modeling and calculation of physical quantities.
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Affiliation(s)
- H Ding
- Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.
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36
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Yuan HQ, Jiao L, Singleton J, Balakirev FF, Chen GF, Luo JL, Wang NL. The magnetoresistance and Hall effect in CeFeAsO: a high magnetic field study. ACTA ACUST UNITED AC 2011. [DOI: 10.1088/1742-6596/273/1/012110] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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37
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Lipscombe OJ, Chen GF, Fang C, Perring TG, Abernathy DL, Christianson AD, Egami T, Wang N, Hu J, Dai P. Spin waves in the (π,0) magnetically ordered iron chalcogenide Fe1.05Te. Phys Rev Lett 2011; 106:057004. [PMID: 21405424 DOI: 10.1103/physrevlett.106.057004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Indexed: 05/30/2023]
Abstract
We use neutron scattering to show that spin waves in the iron chalcogenide Fe(1.05)Te display novel dispersion clearly different from both the first principles density functional calculations and recent observations in the related iron pnictide CaFe(2)As(2). By fitting to a Heisenberg Hamiltonian, we find that although the nearest-neighbor exchange couplings in the two systems are quite different, their next-nearest-neighbor (NNN) couplings are similar. This suggests that superconductivity in the pnictides and chalcogenides share a common magnetic origin that is intimately associated with the NNN magnetic coupling between the irons.
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Affiliation(s)
- O J Lipscombe
- The University of Tennessee, Knoxville, Tennessee 37996-1200, USA
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Nakayama K, Sato T, Richard P, Kawahara T, Sekiba Y, Qian T, Chen GF, Luo JL, Wang NL, Ding H, Takahashi T. Angle-resolved photoemission spectroscopy of the iron-chalcogenide superconductor Fe1.03Te0.7Se0.3: strong coupling behavior and the universality of interband scattering. Phys Rev Lett 2010; 105:197001. [PMID: 21231191 DOI: 10.1103/physrevlett.105.197001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2009] [Revised: 03/10/2010] [Indexed: 05/30/2023]
Abstract
We have performed angle-resolved photoemission spectroscopy of the iron-chalcogenide superconductor Fe1.03Te0.7Se0.3 to investigate the electronic structure relevant to superconductivity. We observed a holelike Fermi surface (FS) and an electronlike FS at the Brillouin zone center and corner, respectively, which are nearly nested by the Q∼(π,π) wave vector. We do not find evidence for the nesting instability with Q∼(π+δ,0) reminiscent of the antiferromagnetic order in the parent compound Fe1+yTe. We have observed an isotropic superconducting (SC) gap along the holelike FS with the gap size Δ of ∼4 meV (2Δ/kBTc ∼ 7), demonstrating the strong-coupling superconductivity. The observed similarity of low-energy electronic excitations between iron-chalcogenides and iron-arsenides strongly suggests that common interactions which involve Q∼(π,π) scattering are responsible for the SC pairing.
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Affiliation(s)
- K Nakayama
- Department of Physics, Tohoku University, Sendai 980-8578, Japan
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39
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Liu H, Chen GF, Zhang W, Zhao L, Liu G, Xia TL, Jia X, Mu D, Liu S, He S, Peng Y, He J, Chen Z, Dong X, Zhang J, Wang G, Zhu Y, Xu Z, Chen C, Zhou XJ. Unusual electronic structure and observation of dispersion kink in CeFeAsO parent compound of FeAs-based superconductors. Phys Rev Lett 2010; 105:027001. [PMID: 20867728 DOI: 10.1103/physrevlett.105.027001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Indexed: 05/29/2023]
Abstract
We report the first comprehensive high-resolution angle-resolved photoemission measurements on CeFeAsO, a parent compound of FeAs-based high temperature superconductors with a magnetic-structural transition at ∼150 K. In the magnetic-ordering state, four holelike Fermi surface sheets are observed near Γ(0,0), and the Fermi surface near M(±π,±π) shows a tiny electronlike pocket at M surrounded by four strong spots. The unusual Fermi surface topology deviates strongly from the band structure calculations. The electronic signature of the magnetic-structural transition shows up in the dramatic change of the quasiparticle scattering rate. A dispersion kink at ∼25 meV is observed for the first time in the parent compound of Fe-based superconductors.
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Affiliation(s)
- Haiyun Liu
- National Lab for Superconductivity, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
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40
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Torchinsky DH, Chen GF, Luo JL, Wang NL, Gedik N. Band-dependent quasiparticle dynamics in single crystals of the Ba(0.6)K(0.4)Fe2As2 superconductor revealed by pump-probe spectroscopy. Phys Rev Lett 2010; 105:027005. [PMID: 20867732 DOI: 10.1103/physrevlett.105.027005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Revised: 02/15/2010] [Indexed: 05/29/2023]
Abstract
We report on band-dependent quasiparticle dynamics in Ba(0.6)K(0.4)Fe2As2 (Tc=37 K) measured using ultrafast pump-probe spectroscopy. In the superconducting state, we observe two distinct relaxation processes: a fast component whose decay rate increases linearly with excitation density and a slow component with an excitation density independent decay rate. We argue that these two components reflect the recombination of quasiparticles in the two hole bands through intraband and interband processes. We also find that the thermal recombination rate of quasiparticles increases quadratically with temperature. The temperature and excitation density dependence of the decays indicates fully gapped hole bands and nodal or very anisotropic electron bands.
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Affiliation(s)
- Darius H Torchinsky
- Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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41
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Richard P, Nakayama K, Sato T, Neupane M, Xu YM, Bowen JH, Chen GF, Luo JL, Wang NL, Dai X, Fang Z, Ding H, Takahashi T. Observation of Dirac cone electronic dispersion in BaFe2As2. Phys Rev Lett 2010; 104:137001. [PMID: 20481905 DOI: 10.1103/physrevlett.104.137001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2009] [Revised: 12/17/2009] [Indexed: 05/29/2023]
Abstract
We performed an angle-resolved photoemission spectroscopy study of BaFe2As2, which is the parent compound of the so-called 122 phase of the iron-pnictide high-temperature superconductors. We reveal the existence of a Dirac cone in the electronic structure of this material below the spin-density-wave temperature, which is responsible for small spots of high photoemission intensity at the Fermi level. Our analysis suggests that the cone is slightly anisotropic and its apex is located very near the Fermi level, leading to tiny Fermi surface pockets. The bands forming the cone show an anisotropic leading edge gap away from the cone that suggests a nodal spin-density-wave description.
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Affiliation(s)
- P Richard
- WPI Research Center, Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
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42
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Chia EEM, Talbayev D, Zhu JX, Yuan HQ, Park T, Thompson JD, Panagopoulos C, Chen GF, Luo JL, Wang NL, Taylor AJ. Ultrafast pump-probe study of phase separation and competing orders in the underdoped (Ba,K)Fe2As2 superconductor. Phys Rev Lett 2010; 104:027003. [PMID: 20366619 DOI: 10.1103/physrevlett.104.027003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2008] [Indexed: 05/29/2023]
Abstract
We report measurements of quasiparticle relaxation dynamics in the high-temperature superconductor (Ba,K)Fe2As2 in optimally doped, underdoped, and undoped regimes. In the underdoped sample, spin-density wave (SDW) order forms at approximately 85 K, followed by superconductivity at approximately 28 K. We find the emergence of a normal-state order that suppresses SDW at a temperature T{*} approximately 60 K and argue that this normal-state order is a precursor to superconductivity.
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Affiliation(s)
- Elbert E M Chia
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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43
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de la Cruz C, Hu WZ, Li S, Huang Q, Lynn JW, Green MA, Chen GF, Wang NL, Mook HA, Si Q, Dai P. Lattice distortion and magnetic quantum phase transition in CeFeAs(1-x)P(x)O. Phys Rev Lett 2010; 104:017204. [PMID: 20366390 DOI: 10.1103/physrevlett.104.017204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2009] [Indexed: 05/29/2023]
Abstract
We use neutron diffraction to study the structural and magnetic phase diagram of CeFeAs(1-x)P(x)O. We find that replacing the larger arsenic with smaller phosphorus in CeFeAs(1-x)P(x)O simultaneously suppresses the AFM order and orthorhombic distortion near x=0.4, thus suggesting the presence of a magnetic quantum critical point. Our detailed structural analysis reveals that the pnictogen height is an important controlling parameter for their electronic and magnetic properties, and may play an important role in electron pairing and superconductivity of these materials.
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Affiliation(s)
- Clarina de la Cruz
- Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996-1200, USA
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Sato T, Nakayama K, Sekiba Y, Richard P, Xu YM, Souma S, Takahashi T, Chen GF, Luo JL, Wang NL, Ding H. Band structure and fermi surface of an extremely overdoped iron-based superconductor KFe2As2. Phys Rev Lett 2009; 103:047002. [PMID: 19659391 DOI: 10.1103/physrevlett.103.047002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2008] [Indexed: 05/28/2023]
Abstract
We have performed high-resolution angle-resolved photoemission spectroscopy on heavily overdoped KFe_{2}As_{2} (transition temperature T_{c} = 3 K). We observed several renormalized bands near the Fermi level with a renormalization factor of 2-4. While the Fermi surface around the Brillouin-zone center is qualitatively similar to that of optimally doped Ba_{1-x}K_{x}Fe_{2}As_{2} (x = 0.4; T_{c} = 37 K), the Fermi surface topology around the zone corner (M point) is markedly different: the two electron Fermi surface pockets are completely absent due to an excess of hole doping. This result indicates that the electronic states around the M point play an important role in the high-T_{c} superconductivity of Ba_{1-x}K_{x}Fe_{2}As_{2} and suggests that the interband scattering via the antiferromagnetic wave vector essentially controls the T_{c} value in the overdoped region.
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Affiliation(s)
- T Sato
- Department of Physics, Tohoku University, Sendai 980-8578, Japan and TRiP, Japan Science and Technology Agency (JST), Kawaguchi 332-0012, Japan
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45
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Xia Y, Qian D, Wray L, Hsieh D, Chen GF, Luo JL, Wang NL, Hasan MZ. Fermi surface topology and low-lying quasiparticle dynamics of parent Fe1+xTe/Se superconductor. Phys Rev Lett 2009; 103:037002. [PMID: 19659308 DOI: 10.1103/physrevlett.103.037002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2009] [Indexed: 05/28/2023]
Abstract
We report the first photoemission study of Fe1+xTe-the host compound of the newly discovered iron-chalcogenide superconductors (maximum Tc approximately 27 K). Our results reveal a pair of nearly electron-hole compensated Fermi pockets, strong Fermi velocity renormalization, and an absence of a spin-density-wave gap. A shadow hole pocket is observed at the "X" point of the Brillouin zone which is consistent with a long-range ordered magnetostructural ground state. No signature of Fermi surface nesting instability associated with Q=(pi/2,pi/2) is observed. Our results collectively reveal that the Fe1+xTe series is different from the undoped phases of the high Tc pnictides and likely harbor an unusual mechanism for superconductivity and magnetic order.
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Affiliation(s)
- Y Xia
- Joseph Henry Laboratories of Physics, Department of Physics, Princeton Center for Complex Materials, Princeton University, Princeton, New Jersey 08544, USA
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Abstract
Specific heat, resistivity, susceptibility, and Hall coefficient measurements were performed on high-quality single-crystalline Na_{1-delta}FeAs. This compound is found to undergo three successive phase transitions at around 52, 41, and 23 K, which correspond to structural, magnetic, and superconducting transitions, respectively. The Hall effect result indicates the development of energy gap at low temperature due to the occurrence of spin-density-wave instability. Our results provide direct experimental evidence of the magnetic ordering in the nearly stoichiometric NaFeAs.
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Affiliation(s)
- G F Chen
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
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47
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Carlo JP, Uemura YJ, Goko T, Macdougall GJ, Rodriguez JA, Yu W, Luke GM, Dai P, Shannon N, Miyasaka S, Suzuki S, Tajima S, Chen GF, Hu WZ, Luo JL, Wang NL. Static magnetic order and superfluid density of RFeAs(O,F) (R=La,Nd,Ce) and LaFePO studied by muon spin relaxation: unusual similarities with the behavior of cuprate superconductors. Phys Rev Lett 2009; 102:087001. [PMID: 19257776 DOI: 10.1103/physrevlett.102.087001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2008] [Indexed: 05/27/2023]
Abstract
Muon spin relaxation measurements in iron-oxypnictide systems have revealed: (1) commensurate long-range order in undoped LaFeAsO; (2) a Bessel function line shape in LaFeAs(O0.97F0.03) which indicates possible incommensurate or stripe magnetism; (3) anomalous weak magnetism existing in superconducting LaFePO, CeFeAs(O0.084F0.16), and NdFeAs(O0.88F0.12) but absent in superconducting LaFeAs(O0.92F0.08); and (4) scaling of the superfluid density with T_{c} in the Ce-, La-, and Nd-FeAs superconductors following a nearly linear relationship found in cuprates.
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Affiliation(s)
- J P Carlo
- Department of Physics, Columbia University, New York, New York 10027, USA
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48
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Richard P, Sato T, Nakayama K, Souma S, Takahashi T, Xu YM, Chen GF, Luo JL, Wang NL, Ding H. Angle-resolved photoemission spectroscopy of the Fe-Based Ba0.6K0.4Fe2As2 high temperature superconductor: evidence for an orbital selective electron-mode coupling. Phys Rev Lett 2009; 102:047003. [PMID: 19257465 DOI: 10.1103/physrevlett.102.047003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Indexed: 05/27/2023]
Abstract
We have performed an angle-resolved photoemission spectroscopy study of the new superconductor Ba0.6K0.4Fe2As2 in the low energy range. We report the observation of an anomaly around 25 meV in the dispersion of superconducting Ba0.6K0.4Fe2As2 samples that nearly vanishes above T_{c}. The energy scale of the related mode (13+/-2 meV) and its strong dependence on orbital and temperature indicates that it is unlikely related to phonons. Moreover, the momentum locations of the kink can be connected by the antiferromagnetic wave vector. Our results point towards an unconventional electronic origin of the mode and the superconducting pairing in the Fe-based superconductors, and strongly support the antiphase s-wave pairing symmetry.
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Affiliation(s)
- P Richard
- WPI Research Center, Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
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49
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Hu WZ, Dong J, Li G, Li Z, Zheng P, Chen GF, Luo JL, Wang NL. Origin of the spin density wave instability in AFe2As2 (A=Ba,Sr) as revealed by optical spectroscopy. Phys Rev Lett 2008. [PMID: 19113746 DOI: 10.1088/0256-307x/25/9/083] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We performed optical spectroscopy measurement on single crystals of BaFe2As2 and SrFe2As2, the parent compounds of FeAs-based superconductors. Both are found to be quite metallic with fairly large plasma frequencies at high temperature. Upon entering the spin-density-wave state, the formation of partial energy gaps was clearly observed with the surprising presence of two different energy scales. A large part of the Drude component was removed by the gapping of Fermi surfaces. Meanwhile, the carrier scattering rate was even more dramatically reduced. We elaborate that the spin-density-wave instability is more likely to be driven by the Fermi surface nesting of itinerant electrons than a local-exchange mechanism.
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Affiliation(s)
- W Z Hu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
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50
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Hu WZ, Dong J, Li G, Li Z, Zheng P, Chen GF, Luo JL, Wang NL. Origin of the spin density wave instability in AFe2As2 (A=Ba,Sr) as revealed by optical spectroscopy. Phys Rev Lett 2008; 101:257005. [PMID: 19113746 DOI: 10.1103/physrevlett.101.257005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Revised: 08/05/2008] [Indexed: 05/27/2023]
Abstract
We performed optical spectroscopy measurement on single crystals of BaFe2As2 and SrFe2As2, the parent compounds of FeAs-based superconductors. Both are found to be quite metallic with fairly large plasma frequencies at high temperature. Upon entering the spin-density-wave state, the formation of partial energy gaps was clearly observed with the surprising presence of two different energy scales. A large part of the Drude component was removed by the gapping of Fermi surfaces. Meanwhile, the carrier scattering rate was even more dramatically reduced. We elaborate that the spin-density-wave instability is more likely to be driven by the Fermi surface nesting of itinerant electrons than a local-exchange mechanism.
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Affiliation(s)
- W Z Hu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
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