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Xie T, Eberharter AA, Xing J, Nishimoto S, Brando M, Khanenko P, Sichelschmidt J, Turrini AA, Mazzone DG, Naumov PG, Sanjeewa LD, Harrison N, Sefat AS, Normand B, Läuchli AM, Podlesnyak A, Nikitin SE. Complete field-induced spectral response of the spin-1/2 triangular-lattice antiferromagnet CsYbSe 2. NPJ Quantum Mater 2023; 8:48. [PMID: 38666238 PMCID: PMC11041694 DOI: 10.1038/s41535-023-00580-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 09/11/2023] [Indexed: 04/28/2024]
Abstract
Fifty years after Anderson's resonating valence-bond proposal, the spin-1/2 triangular-lattice Heisenberg antiferromagnet (TLHAF) remains the ultimate platform to explore highly entangled quantum spin states in proximity to magnetic order. Yb-based delafossites are ideal candidate TLHAF materials, which allow experimental access to the full range of applied in-plane magnetic fields. We perform a systematic neutron scattering study of CsYbSe2, first proving the Heisenberg character of the interactions and quantifying the second-neighbor coupling. We then measure the complex evolution of the excitation spectrum, finding extensive continuum features near the 120°-ordered state, throughout the 1/3-magnetization plateau and beyond this up to saturation. We perform cylinder matrix-product-state (MPS) calculations to obtain an unbiased numerical benchmark for the TLHAF and spectacular agreement with the experimental spectra. The measured and calculated longitudinal spectral functions reflect the role of multi-magnon bound and scattering states. These results provide valuable insight into unconventional field-induced spin excitations in frustrated quantum materials.
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Affiliation(s)
- Tao Xie
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
| | - A. A. Eberharter
- Institut für Theoretische Physik, Universität Innsbruck, Innsbruck, Austria
| | - Jie Xing
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
| | - S. Nishimoto
- Department of Physics, Technical University Dresden, 01069 Dresden, Germany
- Institute for Theoretical Solid State Physics, IFW Dresden, 01069 Dresden, Germany
| | - M. Brando
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, D-01187 Dresden, Germany
| | - P. Khanenko
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, D-01187 Dresden, Germany
| | - J. Sichelschmidt
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, D-01187 Dresden, Germany
| | - A. A. Turrini
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen-PSI, Switzerland
| | - D. G. Mazzone
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen-PSI, Switzerland
| | - P. G. Naumov
- Quantum Criticality and Dynamics Group, Paul Scherrer Institut, CH-5232 Villigen-PSI, Switzerland
- Orange Quantum Systems B.V., Elektronicaweg 2, 2628 XG Delft, The Netherlands
| | - L. D. Sanjeewa
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
| | - N. Harrison
- National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545 USA
| | - Athena S. Sefat
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
| | - B. Normand
- Laboratory for Theoretical and Computational Physics, Paul Scherrer Institut, CH-5232 Villigen-PSI, Switzerland
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - A. M. Läuchli
- Laboratory for Theoretical and Computational Physics, Paul Scherrer Institut, CH-5232 Villigen-PSI, Switzerland
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - A. Podlesnyak
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
| | - S. E. Nikitin
- Quantum Criticality and Dynamics Group, Paul Scherrer Institut, CH-5232 Villigen-PSI, Switzerland
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Podlesnyak A, Nikitin SE, Ehlers G. Low-energy spin dynamics in rare-earth perovskite oxides. J Phys Condens Matter 2021; 33:403001. [PMID: 34252895 DOI: 10.1088/1361-648x/ac1367] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 07/12/2021] [Indexed: 06/13/2023]
Abstract
We review recent studies of spin dynamics in rare-earth orthorhombic perovskite oxides of the type RMO3, where R is a rare-earth ion and M is a transition-metal ion, using single-crystal inelastic neutron scattering (INS). After a short introduction to the magnetic INS technique in general, the results of INS experiments on both transition-metal and rare-earth subsystems for four selected compounds (YbFeO3, TmFeO3, YFeO3, YbAlO3) are presented. We show that the spectrum of magnetic excitations consists of two types of collective modes that are well separated in energy: gapped magnons with a typical bandwidth of <70 meV, associated with the antiferromagnetically (AFM) ordered transition-metal subsystem, and AFM fluctuations of <5 meV within the rare-earth subsystem, with no hybridization of those modes. We discuss the high-energy conventional magnon excitations of the 3dsubsystem only briefly, and focus in more detail on the spectacular dynamics of the rare-earth sublattice in these materials. We observe that the nature of the ground state and the low-energy excitation strongly depends on the identity of the rare-earth ion. In the case of non-Kramers ions, the low-symmetry crystal field completely eliminates the degeneracy of the multiplet state, creating a rich magnetic field-temperature phase diagram. In the case of Kramers ions, the resulting ground state is at least a doublet, which can be viewed as an effective quantum spin-1/2. Equally important is the fact that in Yb-based materials the nearest-neighbor exchange interaction dominates in one direction, despite the three-dimensional nature of the orthoperovskite crystal structure. The observation of a fractional spinon continuum and quantum criticality in YbAlO3demonstrates that Kramers rare-earth based magnets can provide realizations of various aspects of quantum low-dimensional physics.
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Affiliation(s)
- A Podlesnyak
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States of America
| | - S E Nikitin
- Paul Scherrer Institute, CH-5232 Villigen, Switzerland
| | - G Ehlers
- Neutron Technologies Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States of America
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Nikitin SE, Nishimoto S, Fan Y, Wu J, Wu LS, Sukhanov AS, Brando M, Pavlovskii NS, Xu J, Vasylechko L, Yu R, Podlesnyak A. Publisher Correction: Multiple fermion scattering in the weakly coupled spin-chain compound YbAlO 3. Nat Commun 2021; 12:4428. [PMID: 34267197 PMCID: PMC8282856 DOI: 10.1038/s41467-021-24744-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Affiliation(s)
- S E Nikitin
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany. .,Institut für Festkörper- und Materialphysik, Technische Universität Dresden, Dresden, Germany. .,Paul Scherrer Institute, Villigen PSI, Villigen, Switzerland.
| | - S Nishimoto
- Department of Physics, Technical University Dresden, Dresden, Germany.,Institute for Theoretical Solid State Physics, IFW Dresden, Dresden, Germany
| | - Y Fan
- Department of Physics and Beijing Key Laboratory of Opto-Electronic Functional Materials and Micro-Nano Devices, Renmin University of China, Beijing, China.,Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - J Wu
- Tsung-Dao Lee Institute and School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, China
| | - L S Wu
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA.,Department of Physics, Southern University of Science and Technology, Shenzhen, China
| | - A S Sukhanov
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany.,Institut für Festkörper- und Materialphysik, Technische Universität Dresden, Dresden, Germany
| | - M Brando
- Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - N S Pavlovskii
- Kirensky Institute of Physics, Federal Research Center, Krasnoyarsk, Russia
| | - J Xu
- Helmholtz-Zentrum Berlin für Materialien und Energie, Berlin, Germany.,Heinz Maier-Leibnitz Zentrum, Technische Universität München, Garching, Germany
| | - L Vasylechko
- Lviv Polytechnic National University, Lviv, Ukraine
| | - R Yu
- Department of Physics and Beijing Key Laboratory of Opto-Electronic Functional Materials and Micro-Nano Devices, Renmin University of China, Beijing, China.
| | - A Podlesnyak
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, USA
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Kolesnikov AI, Anovitz LM, Hawthorne FC, Podlesnyak A, Schenter GK. Effect of fine-tuning pore structures on the dynamics of confined water. J Chem Phys 2019; 150:204706. [DOI: 10.1063/1.5096771] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- A. I. Kolesnikov
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - L. M. Anovitz
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - F. C. Hawthorne
- Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - A. Podlesnyak
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - G. K. Schenter
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 93352, USA
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Wu LS, Nikitin SE, Wang Z, Zhu W, Batista CD, Tsvelik AM, Samarakoon AM, Tennant DA, Brando M, Vasylechko L, Frontzek M, Savici AT, Sala G, Ehlers G, Christianson AD, Lumsden MD, Podlesnyak A. Tomonaga-Luttinger liquid behavior and spinon confinement in YbAlO 3. Nat Commun 2019; 10:698. [PMID: 30741939 PMCID: PMC6370837 DOI: 10.1038/s41467-019-08485-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [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: 06/11/2018] [Accepted: 01/14/2019] [Indexed: 11/09/2022] Open
Abstract
Low dimensional quantum magnets are interesting because of the emerging collective behavior arising from strong quantum fluctuations. The one-dimensional (1D) S = 1/2 Heisenberg antiferromagnet is a paradigmatic example, whose low-energy excitations, known as spinons, carry fractional spin S = 1/2. These fractional modes can be reconfined by the application of a staggered magnetic field. Even though considerable progress has been made in the theoretical understanding of such magnets, experimental realizations of this low-dimensional physics are relatively rare. This is particularly true for rare-earth-based magnets because of the large effective spin anisotropy induced by the combination of strong spin-orbit coupling and crystal field splitting. Here, we demonstrate that the rare-earth perovskite YbAlO3 provides a realization of a quantum spin S = 1/2 chain material exhibiting both quantum critical Tomonaga-Luttinger liquid behavior and spinon confinement-deconfinement transitions in different regions of magnetic field-temperature phase diagram.
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Affiliation(s)
- L S Wu
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
- Department of Physics, Southern University of Science and Technology, 518055, Shenzhen, China.
| | - S E Nikitin
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187, Dresden, Germany
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01069, Dresden, Germany
| | - Z Wang
- Department of Physics and Astronomy, The University of Tennessee, Knoxville, TN, 37996, USA
| | - W Zhu
- Westlake Institute of Advanced Study, 310024, Hangzhou, P. R. China
- Theoretical Division, T-4 and CNLS, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - C D Batista
- Department of Physics and Astronomy, The University of Tennessee, Knoxville, TN, 37996, USA
- Shull-Wollan Center, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - A M Tsvelik
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, NY, 11973, USA
| | - A M Samarakoon
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - D A Tennant
- Shull-Wollan Center, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - M Brando
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Str. 40, 01187, Dresden, Germany
| | - L Vasylechko
- Lviv Polytechnic National University, Lviv, 79013, Ukraine
| | - M Frontzek
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - A T Savici
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - G Sala
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - G Ehlers
- Neutron Technologies Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - A D Christianson
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - M D Lumsden
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - A Podlesnyak
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
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Savchenkov PS, Alekseev PA, Podlesnyak A, Kolesnikov AI, Nemkovski KS. Intermediate-valence state of the Sm and Eu in SmB 6 and EuCu 2Si 2: neutron spectroscopy data and analysis. J Phys Condens Matter 2018; 30:055801. [PMID: 29324435 DOI: 10.1088/1361-648x/aaa1aa] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Magnetic neutron scattering data for Sm (SmB6, Sm(Y)S) and Eu (EuCu2Si2-x Ge x ) intermediate-valence compounds have been analysed in terms of a generalized model of the intermediate-radius exciton. Special attention is paid to the correlation between the average ion's valence and parameters of the low-energy excitation in the neutron spectra, such as the resonance mode, including its magnetic form factor. Along with specific features of the formation of the intermediate-valence state for Sm and Eu ions, common physical mechanisms have been revealed for systems based on these elements from the middle of the rare-earth series. A consistent description of the existing experimental data has been obtained by using the concept of a loosely bound hole for the Eu f-electron shell in the intermediate-valence state, in analogy with the previously established loosely bound electron model for the Sm ion.
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Affiliation(s)
- P S Savchenkov
- National Research Nuclear University MEPhI, 115409, Moscow, Russia. National Research Centre Kurchatov Institute, 123182, Moscow, Russia
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7
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Chatterji T, Demmel F, Jalarvo N, Podlesnyak A, Kumar CMN, Xiao Y, Brückel T. Quasielastic and low-energy inelastic neutron scattering study of HoCrO 3 by high resolution time-of-flight neutron spectroscopy. J Phys Condens Matter 2017; 29:475802. [PMID: 29095702 DOI: 10.1088/1361-648x/aa9245] [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] [Indexed: 06/07/2023]
Abstract
In order to understand the origin of the huge quasielastic magnetic scattering observed previously with a back-scattering neutron spectrometer, we have re-investigated the low energy excitations in HoCrO3 by inelastic neutron scattering in a much wider energy range with time-of-flight neutron spectrometers. The inelastic signals are due to the excitations between the ground state doublet of the Ho ion. The quasielastic signal is due to the fluctuation of the disordered Ho moments. At low temperature the intensity of quasielastic scattering is small. It starts increasing as the temperature increases above 30 K. At the same temperature, the elastic intensity due to Ho moment ordering decreases in a similar way. This observation strengthens the hypothesis that the quasielastic scattering is due the fluctuations of the disordered Ho moments. The time scale of fluctuations has been determine from the quasielastic scattering and was found to vary from about 22 ps at [Formula: see text] K to about 2.5 ps at [Formula: see text] K. The stretched exponential line shape indicates a distribution of decay rates at low temperatures.
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Affiliation(s)
- T Chatterji
- Institut Laue-Langevin, 71 Avenue des Martyrs, 38000 Grenoble, France
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8
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Li Y, Yin Z, Wang X, Tam DW, Abernathy DL, Podlesnyak A, Zhang C, Wang M, Xing L, Jin C, Haule K, Kotliar G, Maier TA, Dai P. Orbital Selective Spin Excitations and their Impact on Superconductivity of LiFe_{1-x}Co_{x}As. Phys Rev Lett 2016; 116:247001. [PMID: 27367401 DOI: 10.1103/physrevlett.116.247001] [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: 01/18/2016] [Indexed: 06/06/2023]
Abstract
We use neutron scattering to study spin excitations in single crystals of LiFe_{0.88}Co_{0.12}As, which is located near the boundary of the superconducting phase of LiFe_{1-x}Co_{x}As and exhibits non-Fermi-liquid behavior indicative of a quantum critical point. By comparing spin excitations of LiFe_{0.88}Co_{0.12}As with a combined density functional theory and dynamical mean field theory calculation, we conclude that wave-vector correlated low energy spin excitations are mostly from the d_{xy} orbitals, while high-energy spin excitations arise from the d_{yz} and d_{xz} orbitals. Unlike most iron pnictides, the strong orbital selective spin excitations in the LiFeAs family cannot be described by an anisotropic Heisenberg Hamiltonian. While the evolution of low-energy spin excitations of LiFe_{1-x}Co_{x}As is consistent with the electron-hole Fermi surface nesting conditions for the d_{xy} orbital, the reduced superconductivity in LiFe_{0.88}Co_{0.12}As suggests that Fermi surface nesting conditions for the d_{yz} and d_{xz} orbitals are also important for superconductivity in iron pnictides.
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Affiliation(s)
- Yu Li
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA
| | - Zhiping Yin
- Center for Advanced Quantum Studies and Department of Physics, Beijing Normal University, Beijing 100875, China
- Department of Physics, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Xiancheng Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - David W Tam
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA
| | - D L Abernathy
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - A Podlesnyak
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Chenglin Zhang
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA
| | - Meng Wang
- Department of Physics, University of California, Berkeley, California 94720, USA
| | - Lingyi Xing
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Changqing Jin
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - Kristjan Haule
- Department of Physics, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Gabriel Kotliar
- Department of Physics, Rutgers University, Piscataway, New Jersey 08854, USA
- Brookhaven National Laboratory, Upton, New York 11973-5000, USA
| | - Thomas A Maier
- Center for Nanophase Materials Sciences and Computer Science and Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Pengcheng Dai
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA
- Center for Advanced Quantum Studies and Department of Physics, Beijing Normal University, Beijing 100875, China
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9
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Wu LS, Gannon WJ, Zaliznyak IA, Tsvelik AM, Brockmann M, Caux JS, Kim MS, Qiu Y, Copley JRD, Ehlers G, Podlesnyak A, Aronson MC. Orbital-exchange and fractional quantum number excitations in an f-electron metal, Yb2Pt2Pb. Science 2016; 352:1206-10. [DOI: 10.1126/science.aaf0981] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 04/29/2016] [Indexed: 11/02/2022]
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Stone MB, Niedziela JL, Abernathy DL, DeBeer-Schmitt L, Ehlers G, Garlea O, Granroth GE, Graves-Brook M, Kolesnikov AI, Podlesnyak A, Winn B. A comparison of four direct geometry time-of-flight spectrometers at the Spallation Neutron Source. Rev Sci Instrum 2014; 85:045113. [PMID: 24784665 DOI: 10.1063/1.4870050] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The Spallation Neutron Source at Oak Ridge National Laboratory now hosts four direct geometry time-of-flight chopper spectrometers. These instruments cover a range of wave-vector and energy transfer space with varying degrees of neutron flux and resolution. The regions of reciprocal and energy space available to measure at these instruments are not exclusive and overlap significantly. We present a direct comparison of the capabilities of this instrumentation, conducted by data mining the instrument usage histories, and specific scanning regimes. In addition, one of the common science missions for these instruments is the study of magnetic excitations in condensed matter systems. We have measured the powder averaged spin wave spectra in one particular sample using each of these instruments, and use these data in our comparisons.
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Affiliation(s)
- M B Stone
- Quantum Condensed Matter Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - J L Niedziela
- Instrument and Source Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - D L Abernathy
- Quantum Condensed Matter Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - L DeBeer-Schmitt
- Instrument and Source Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - G Ehlers
- Quantum Condensed Matter Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - O Garlea
- Quantum Condensed Matter Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - G E Granroth
- Neutron Data Analysis and Visualization Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - M Graves-Brook
- Instrument and Source Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - A I Kolesnikov
- Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - A Podlesnyak
- Quantum Condensed Matter Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - B Winn
- Quantum Condensed Matter Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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11
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Kim MG, Tucker GS, Pratt DK, Ran S, Thaler A, Christianson AD, Marty K, Calder S, Podlesnyak A, Bud'ko SL, Canfield PC, Kreyssig A, Goldman AI, McQueeney RJ. Magnonlike dispersion of spin resonance in Ni-doped BaFe2As2. Phys Rev Lett 2013; 110:177002. [PMID: 23679760 DOI: 10.1103/physrevlett.110.177002] [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: 01/21/2013] [Indexed: 06/02/2023]
Abstract
Inelastic neutron scattering measurements on Ba(Fe0.963Ni0.037)2As2 manifest a neutron spin resonance in the superconducting state with anisotropic dispersion within the Fe layer. Whereas the resonance is sharply peaked at the antiferromagnetic (AFM) wave vector Q(AFM) along the orthorhombic a axis, the resonance disperses upwards away from Q(AFM) along the b axis. In contrast to the downward dispersing resonance and hourglass shape of the spin excitations in superconducting cuprates, the resonance in electron-doped BaFe2As2 compounds possesses a magnonlike upwards dispersion.
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Affiliation(s)
- M G Kim
- Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
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12
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Frontzek M, Ehlers G, Podlesnyak A, Cao H, Matsuda M, Zaharko O, Aliouane N, Barilo S, Shiryaev SV. Magnetic structure of CuCrO₂: a single crystal neutron diffraction study. J Phys Condens Matter 2012; 24:016004. [PMID: 22155990 DOI: 10.1088/0953-8984/24/1/016004] [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] [Indexed: 05/31/2023]
Abstract
This paper presents results of a recent study of multiferroic CuCrO(2) by means of single crystal neutron diffraction. This system has two close magnetic phase transitions at T(N) = 24.2 K and T(mf) = 23.6 K. The low temperature magnetic structure below T(mf) is unambiguously determined to be a fully three-dimensional proper screw. Between T(N) and T(mf) antiferromagnetic order is found that is essentially two-dimensional. In this narrow temperature range, magnetic near neighbor correlations are still long range in the (H,K) plane, whereas nearest neighbors along the L direction are uncorrelated. Thus, the multiferroic state is realized only in the low temperature three-dimensional state and not in the two-dimensional state.
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Affiliation(s)
- M Frontzek
- Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
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13
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Stone MB, Podlesnyak A, Ehlers G, Huq A, Samulon EC, Shapiro MC, Fisher IR. Persistence of magnons in a site-diluted dimerized frustrated antiferromagnet. J Phys Condens Matter 2011; 23:416003. [PMID: 21952109 DOI: 10.1088/0953-8984/23/41/416003] [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: 05/31/2023]
Abstract
We present inelastic neutron scattering and thermodynamic measurements characterizing the magnetic excitations in a disordered spin-liquid antiferromagnet with non-magnetic substitution. The parent compound Ba(3)Mn(2)O(8) is a dimerized, quasi-two-dimensional geometrically frustrated quantum disordered antiferromagnet. We substitute this compound with non-magnetic V(5+) for the S=1 Mn(5+) ions, Ba(3)(Mn(1-x)V (x))(2)O(8), and find that the singlet-triplet excitations which dominate the spectrum of the parent compound persist for the full range of substitution examined, up to x=0.3. We also observe additional low-energy magnetic fluctuations which are enhanced at the greatest substitution values.
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Affiliation(s)
- M B Stone
- Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
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Delaire O, Ma J, Marty K, May AF, McGuire MA, Du MH, Singh DJ, Podlesnyak A, Ehlers G, Lumsden MD, Sales BC. Giant anharmonic phonon scattering in PbTe. Nat Mater 2011; 10:614-9. [PMID: 21642983 DOI: 10.1038/nmat3035] [Citation(s) in RCA: 174] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2011] [Accepted: 04/22/2011] [Indexed: 05/24/2023]
Abstract
Understanding the microscopic processes affecting the bulk thermal conductivity is crucial to develop more efficient thermoelectric materials. PbTe is currently one of the leading thermoelectric materials, largely thanks to its low thermal conductivity. However, the origin of this low thermal conductivity in a simple rocksalt structure has so far been elusive. Using a combination of inelastic neutron scattering measurements and first-principles computations of the phonons, we identify a strong anharmonic coupling between the ferroelectric transverse optic mode and the longitudinal acoustic modes in PbTe. This interaction extends over a large portion of reciprocal space, and directly affects the heat-carrying longitudinal acoustic phonons. The longitudinal acoustic-transverse optic anharmonic coupling is likely to play a central role in explaining the low thermal conductivity of PbTe. The present results provide a microscopic picture of why many good thermoelectric materials are found near a lattice instability of the ferroelectric type.
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Affiliation(s)
- O Delaire
- Neutron Scattering Science Division, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, USA.
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Podlesnyak A, Russina M, Furrer A, Alfonsov A, Vavilova E, Kataev V, Büchner B, Strässle T, Pomjakushina E, Conder K, Khomskii DI. Spin-state polarons in lightly-hole-doped LaCoO3. Phys Rev Lett 2008; 101:247603. [PMID: 19113665 DOI: 10.1103/physrevlett.101.247603] [Citation(s) in RCA: 5] [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: 04/18/2008] [Indexed: 05/27/2023]
Abstract
Inelastic neutron scattering (INS), electron spin resonance (ESR), and nuclear magnetic resonance (NMR) measurements were employed to establish the origin of the strong magnetic signal in lightly-hole-doped La1-xSrxCoO3, x approximately 0.002. Both INS and ESR low temperature spectra show intense excitations with large effective g factors approximately 10-18. NMR data indicate the creation of extended magnetic clusters. From the Q dependence of the INS magnetic intensity, we conclude that the observed anomalies are caused by the formation of octahedrally shaped spin-state polarons comprising seven Co ions. The present INS, ESR, and NMR data give evidence for two regimes in the lightly-hole-doped samples: (i) T<35 K dominated by spin polarons; (ii) T>35 K dominated by thermally activated magnetic Co3+ ions.
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Affiliation(s)
- A Podlesnyak
- Hahn-Meitner-Institut, Glienicker Strasse 100, Berlin 14109, Germany.
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Pomjakushina E, Conder K, Stingaciu M, Podlesnyak A. Layered and cubic cobaltites grown by floating zone, structural and magnetic properties study. Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308098954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Alekseev PA, Lazukov VN, Tiden NN, Kahn R, Mignot JM, Podlesnyak A, Clementyev ES, Sadikov IP. Magnetic correlations in the CeAl3 heavy-fermion system. CRYSTALLOGR REP+ 2007. [DOI: 10.1134/s106377450703008x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Häfliger P, Podlesnyak A, Conder K, Pomjakushina E, Furrer A. The pseudogap in LSCO-type high-temperature superconductors as seen by neutron crystal-field spectroscopy. PROG SOLID STATE CH 2007. [DOI: 10.1016/j.progsolidstchem.2007.03.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Podlesnyak A, Streule S, Mesot J, Medarde M, Pomjakushina E, Conder K, Tanaka A, Haverkort MW, Khomskii DI. Spin-state transition in LaCoO3: direct neutron spectroscopic evidence of excited magnetic states. Phys Rev Lett 2006; 97:247208. [PMID: 17280319 DOI: 10.1103/physrevlett.97.247208] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2005] [Indexed: 05/13/2023]
Abstract
A gradual spin-state transition occurs in LaCoO3 around T approximately 80-120 K, whose detailed nature remains controversial. We studied this transition by means of inelastic neutron scattering and found that with increasing temperature an excitation at approximately 0.6 meV appears, whose intensity increases with temperature, following the bulk magnetization. Within a model including crystal-field interaction and spin-orbit coupling, we interpret this excitation as originating from a transition between thermally excited states located about 120 K above the ground state. We further discuss the nature of the magnetic excited state in terms of intermediate-spin (t(2g)(5)e(g)(1), S=1) versus high-spin (t(2g)(4)e(g)(2), S=2) states. Since the g factor obtained from the field dependence of the inelastic neutron scattering is g approximately 3, the second interpretation is definitely favored.
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Affiliation(s)
- A Podlesnyak
- Laboratory for Neutron Scattering, ETH Zürich Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
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Tripadus V, Radulescu A, Pieper J, Buchsteiner A, Podlesnyak A, Janssen S, Serban A. Molecular dynamics in triglycine sulphate by cold neutron spectroscopy. Chem Phys 2006. [DOI: 10.1016/j.chemphys.2005.08.042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Conder K, Pomjakushina E, Pomjakushin V, Stingaciu M, Streule S, Podlesnyak A. Oxygen isotope effect on metal-insulator transition in layered cobaltites RBaCo 2O 5.5 (R = Pr, Dy, Ho and Y). J Phys Condens Matter 2005; 17:5813-5820. [PMID: 32397050 DOI: 10.1088/0953-8984/17/37/016] [Citation(s) in RCA: 7] [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] [Indexed: 06/11/2023]
Abstract
Both differential scanning calorimetry and powder neutron diffraction have been applied to investigate an oxygen isotope effect on the metal-insulator (MI) transition in layered cobaltites RBaCo2O5.5 (R = Pr, Dy, Ho and Y). For all the compounds it was found that 18O substitution increases the transition temperature TMI by about 2 K. A small negative isotope-effect coefficient α0∼-0.06 indicates that a delocalization of the pd σ holes in the Co3+ high spin state (rather than a spin-state transition) can be responsible for the MI transition, in agreement with density-functional calculations (Wu 2003 J. Phys.: Condens. Matter 15 503).
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Affiliation(s)
- K Conder
- Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
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Bychkov GL, Shiryaev SV, Soldatov AG, Shestak AS, Barilo SN, Sheptyakov DV, Conder K, Pomjakushina E, Podlesnyak A, Furrer A, Bruetsch R. Crystal growth features and properties of layered rare earth and barium cobaltates. Cryst Res Technol 2005. [DOI: 10.1002/crat.200410356] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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