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Lin JL, Sun Y, He R, Li Y, Zhong Z, Gao P, Zhao X, Zhang Z, Wang ZJ. Colossal Room-Temperature Ferroelectric Polarizations in SrTiO 3/SrRuO 3 Superlattices Induced by Oxygen Vacancies. NANO LETTERS 2022; 22:7104-7111. [PMID: 35984239 DOI: 10.1021/acs.nanolett.2c02175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Artificial superlattices have demonstrated many unique phenomena not found in bulk materials. For this investigation, SrTiO3/SrRuO3 paraelectric/metallic superlattices with various stacking periods were synthesized via pulsed laser deposition. A robust room-temperature ferroelectric polarization (∼46 μC/cm2) was found in the superlattices with 2 unit cell (u.c.) thick SrRuO3 layers, despite the fact that neither SrTiO3 nor SrRuO3 is inherently ferroelectric. Results obtained from atomically resolved elemental mapping and X-ray photoelectron spectroscopy verified that oxygen vacancies accumulated at the SrTiO3/SrRuO3 interfaces, causing lattice distortions and increased tetragonality (c/a). The observed ferroelectric responses can be mainly attributed to the broken spatial inversion symmetry induced by the ordered distribution of oxygen vacancies at the SrTiO3/SrRuO3 interfaces, coupled with the triggering of external electric field. The resulting polarization mechanism induced by oxygen vacancies suggests viable ways for improving the electrical properties of ferroelectric materials, with the goal of expanding the functionality of a range of electronic devices.
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Affiliation(s)
- Jun Liang Lin
- School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China
- Shenyang National Laboratory for Materials Science, Institute of Metal Research (IMR), Chinese Academy of Sciences (CAS), Shenyang 110016, China
- College of Light Industry, Liaoning University, Shenyang 110036, China
| | - Yuanwei Sun
- International Center for Quantum Materials, and Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, 100871, China
| | - Ri He
- Key Laboratory of Magnetic Materials and Devices, Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
| | - Yanxi Li
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
| | - Zhicheng Zhong
- Key Laboratory of Magnetic Materials and Devices, Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
- China Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peng Gao
- International Center for Quantum Materials, and Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing 100871, China
| | - Xiang Zhao
- School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China
| | - Zhidong Zhang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research (IMR), Chinese Academy of Sciences (CAS), Shenyang 110016, China
| | - Zhan Jie Wang
- School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China
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2
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Gu M, Bai YH, Zhang GP, George TF. Spin-phonon dispersion in magnetic materials. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:375802. [PMID: 35793694 DOI: 10.1088/1361-648x/ac7f17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 07/06/2022] [Indexed: 06/15/2023]
Abstract
Microscopic coupling between the electron spin and the lattice vibration is responsible for an array of exotic properties from morphic effects in simple non magnets to magnetodielectric coupling in multiferroic spinels and hematites. Traditionally, a single spin-phonon coupling constant is used to characterize how effectively the lattice can affect the spin, but it is hardly enough to capture novel electromagnetic behaviors to the full extent. Here, we introduce a concept of spin-phonon dispersion to project the spin moment change along the phonon crystal momentum direction, so the entire spin change can be mapped out. Different from the phonon dispersion, the spin-phonon dispersion has both positive and negative frequency branches even in the equilibrium ground state, which correspond to the spin enhancement and spin reduction, respectively. Our study of bcc Fe and hcp Co reveals that the spin force matrix, that is, the second-order spatial derivative of spin moment, is similar to the vibrational force matrix, but its diagonal elements are smaller than the off-diagonal ones. This leads to the distinctive spin-phonon dispersion. The concept of spin-phonon dispersion expands the traditional Elliott-Yafet theory in nonmagnetic materials to the entire Brillouin zone in magnetic materials, thus opening the door to excited states in systems such as CoF2and NiO, where a strong spin-lattice coupling is detected in the THz regime.
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Affiliation(s)
- Mingqiang Gu
- Department of Physics, Southern University of Science and Technology, Shenzhen 518055, People's Republic of China
| | - Y H Bai
- Office of Information Technology, Indiana State University, Terre Haute, IN 47809, United States of America
| | - G P Zhang
- Department of Physics, Indiana State University, Terre Haute, IN 47809, United States of America
| | - Thomas F George
- Departments of Chemistry & Biochemistry and Physics & Astronomy, University of Missouri-St. Louis, St. Louis, MO 63121, United States of America
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3
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Zhang Z, Qian P, Yang X, Wu B, Cai HL, Zhang FM, Wu XS. Manipulating the carrier concentration and phase transition via Nb content in SrTiO 3. Sci Rep 2022; 12:2499. [PMID: 35169173 PMCID: PMC8847566 DOI: 10.1038/s41598-021-03199-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 10/28/2021] [Indexed: 11/24/2022] Open
Abstract
SrTiO3 is a model of the perovskite-like compounds for structural transition which inducing the intriguing physical properties around the critical phase transition temperature TAFD (antiferrodistortive, abbrev. as AFD). Here we report that the electrical transport behavior is a new way to quantify Nb concentration for Nb-doped SrTiO3. The lattice parameter (c), phase transition temperature (TAFD), and the carrier concentration (n) of SrTiO3 may be manipulated by niobium doping. TAFD increases with increasing the niobium content in a rate of about 30 K per (wt%, i.e. niobium element's weight verses total weight) niobium and n in a rate of about 2.5 [Formula: see text] 1020/cm3 per (wt%) niobium.
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Affiliation(s)
- Zhe Zhang
- Institute of Materials Engineering, Nanjing University, Nantong, Jiangsu, 226019, China
- National Laboratory of Solid State Microstructures & Department of Physics, Nanjing University, Nanjing, 210093, China
| | - Peihua Qian
- Institute of Materials Engineering, Nanjing University, Nantong, Jiangsu, 226019, China
- National Laboratory of Solid State Microstructures & Department of Physics, Nanjing University, Nanjing, 210093, China
| | - Xingming Yang
- Institute of Materials Engineering, Nanjing University, Nantong, Jiangsu, 226019, China
- National Laboratory of Solid State Microstructures & Department of Physics, Nanjing University, Nanjing, 210093, China
| | - Baixi Wu
- Institute of Materials Engineering, Nanjing University, Nantong, Jiangsu, 226019, China
- National Laboratory of Solid State Microstructures & Department of Physics, Nanjing University, Nanjing, 210093, China
| | - H L Cai
- Institute of Materials Engineering, Nanjing University, Nantong, Jiangsu, 226019, China
- National Laboratory of Solid State Microstructures & Department of Physics, Nanjing University, Nanjing, 210093, China
| | - F M Zhang
- Institute of Materials Engineering, Nanjing University, Nantong, Jiangsu, 226019, China
- National Laboratory of Solid State Microstructures & Department of Physics, Nanjing University, Nanjing, 210093, China
| | - X S Wu
- Institute of Materials Engineering, Nanjing University, Nantong, Jiangsu, 226019, China.
- National Laboratory of Solid State Microstructures & Department of Physics, Nanjing University, Nanjing, 210093, China.
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4
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Alhaddad M, Zaki ZI, Amin MS. Application of SrRuO3 Nanoparticles Supported with Reduced Graphene Oxide for Degradation of Thiophene Under Visible Light Irradiation. J Inorg Organomet Polym Mater 2021. [DOI: 10.1007/s10904-021-01969-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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5
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Paudel B, Kang KT, Sharma Y, Nakotte H, Yarotski D, Chen A. Symmetry mismatch controlled ferroelastic domain ordering and the functional properties of manganite films on cubic miscut substrates. Phys Chem Chem Phys 2021; 23:16623-16628. [PMID: 34319307 DOI: 10.1039/d1cp01957k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have studied the magnetotransport properties and strain release mechanisms in ferroelastic La0.9Sr0.1MnO3 (LSMO) epitaxial thin films on SrTiO3 (STO)(001) substrates with different miscut angles. The substrate miscut angle plays a critical role in releasing shear strain and has a huge impact on the properties of the films. The strain relaxes by monoclinic distortion for films on low miscut substrates and for higher miscut substrates, the strain relaxation causes the formation of periodic twin domains with larger periodicities. We observe that the Curie temperature (TC) decreases systematically, and magnetoresistance (MR) increases with increasing the miscut angle. Such changes in the magnetic and transport properties could be due to the increased density of phase boundaries (PBs) with the increase of miscut angle. This work provides a way to tailor film microstructures and subsequent functional properties of other complex oxide films on miscut substrates with symmetry mismatch.
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Affiliation(s)
- Binod Paudel
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
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6
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Wang Y, Qian P, Liu Y, Zhang FM, Cai HL, Wu XS, Zhang GP. Modulating the electronic and optical properties for SrTiO 3/LaAlO 3 bilayers treated as the 2D materials by biaxial strains. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:215701. [PMID: 31995526 DOI: 10.1088/1361-648x/ab70c3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The emerging two-dimensional (2D) materials such as graphene have opened the door to industrial applications. Here, we consider the oxide perovskite monolayer of SrTiO3 (STO), LaAlO3 (LAO) and their heterostructures as the 2D transitional metal system. Results show that a band-gap transition from indirect to direct occurs when the separated monolayer STO (indirect band gap of 3.210 eV), and LAO (indirect band gap of 4.024 eV), form the heterostructures (direct band gap of 2.976 eV). The obtained bandgap for the stable bilayers may effectively be modulated by biaxial strains from -12% to 8%. With 12% compressive biaxial strain, the band gap reduces to be 0.23 eV. The optical properties for the stable bilayers are also tuned by the biaxial strain. When the strain increases from compressive strain to tensile strain, the strongest peak of the imaginary part of dielectric function red shifts to lower energy. In comparing with the monolayer STO and LAO, the elastic property enhances obviously for the stable heterostructure, suggesting the heterostructure can be more stable freestanding or may be applied in device fabrications.
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Affiliation(s)
- Yan Wang
- Collaborative Innovation Center of Advanced Microstructures, Laboratory of Solid State Microstructures & School of Physics, Nanjing University, Nanjing 210093, People's Republic of China
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7
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Cui Z, Grutter AJ, Zhou H, Cao H, Dong Y, Gilbert DA, Wang J, Liu YS, Ma J, Hu Z, Guo J, Xia J, Kirby BJ, Shafer P, Arenholz E, Chen H, Zhai X, Lu Y. Correlation-driven eightfold magnetic anisotropy in a two-dimensional oxide monolayer. SCIENCE ADVANCES 2020; 6:eaay0114. [PMID: 32300646 PMCID: PMC7148107 DOI: 10.1126/sciadv.aay0114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Accepted: 01/13/2020] [Indexed: 05/25/2023]
Abstract
Engineering magnetic anisotropy in two-dimensional systems has enormous scientific and technological implications. The uniaxial anisotropy universally exhibited by two-dimensional magnets has only two stable spin directions, demanding 180° spin switching between states. We demonstrate a previously unobserved eightfold anisotropy in magnetic SrRuO3 monolayers by inducing a spin reorientation in (SrRuO3)1/(SrTiO3) N superlattices, in which the magnetic easy axis of Ru spins is transformed from uniaxial 〈001〉 direction (N < 3) to eightfold 〈111〉 directions (N ≥ 3). This eightfold anisotropy enables 71° and 109° spin switching in SrRuO3 monolayers, analogous to 71° and 109° polarization switching in ferroelectric BiFeO3. First-principle calculations reveal that increasing the SrTiO3 layer thickness induces an emergent correlation-driven orbital ordering, tuning spin-orbit interactions and reorienting the SrRuO3 monolayer easy axis. Our work demonstrates that correlation effects can be exploited to substantially change spin-orbit interactions, stabilizing unprecedented properties in two-dimensional magnets and opening rich opportunities for low-power, multistate device applications.
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Affiliation(s)
- Zhangzhang Cui
- Hefei National Laboratory for Physical Sciences at the Microscale, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China
- Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Alexander J. Grutter
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Hua Zhou
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Hui Cao
- Hefei National Laboratory for Physical Sciences at the Microscale, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China
- Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Yongqi Dong
- Hefei National Laboratory for Physical Sciences at the Microscale, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China
- Advanced Photon Source, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Dustin A. Gilbert
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996, USA
| | - Jingyuan Wang
- Department of Physics, University of California, Irvine, Irvine, CA 92697, USA
| | - Yi-Sheng Liu
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Jiaji Ma
- NYU-ECNU Institute of Physics, NYU Shanghai, Shanghai 200122, China
| | - Zhenpeng Hu
- School of Physics, Nankai University, Tianjin 300071, China
| | - Jinghua Guo
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Jing Xia
- Department of Physics, University of California, Irvine, Irvine, CA 92697, USA
| | - Brian J. Kirby
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Padraic Shafer
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Elke Arenholz
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Cornell High Energy Synchrotron Source, Cornell University, Ithaca, NY 14853, USA
| | - Hanghui Chen
- NYU-ECNU Institute of Physics, NYU Shanghai, Shanghai 200122, China
- State Key Laboratory of Precision Spectroscopy, School of Physical and Material Sciences, East China Normal University, Shanghai 200062, China
- Department of Physics, New York University, New York, NY 10027, USA
| | - Xiaofang Zhai
- Hefei National Laboratory for Physical Sciences at the Microscale, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China
- Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Yalin Lu
- Hefei National Laboratory for Physical Sciences at the Microscale, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China
- Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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8
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Biswas A, Talha M, Kashir A, Jeong YH. A thin film perspective on quantum functional oxides. CURRENT APPLIED PHYSICS 2019; 19:207-214. [DOI: 10.1016/j.cap.2018.07.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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9
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Persky E, Kalisky B. Scanning SQUID View of Oxide Interfaces. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1706653. [PMID: 29718543 DOI: 10.1002/adma.201706653] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 02/18/2018] [Indexed: 06/08/2023]
Abstract
The emergence of states of matter in low-dimensional systems is one of the most intriguing topics in condensed matter physics. Interfaces between nonmagnetic, insulating oxides are found to give rise to surprising behaviors, such as metallic conductivity, superconductivity, and magnetism. Sensitive, noninvasive local characterization tools are essential for understanding the electronic and magnetic behavior of these systems. Here, the scanning superconducting quantum interference device (SQUID) technique for local magnetic imaging is described and its contribution to the field of oxide interfaces is reviewed.
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Affiliation(s)
- Eylon Persky
- Department of Physics and Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan, 5290002,, Israel
| | - Beena Kalisky
- Department of Physics and Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan, 5290002,, Israel
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10
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Wang C, Chen C, Chang CH, Tsai HS, Pandey P, Xu C, Böttger R, Chen D, Zeng YJ, Gao X, Helm M, Zhou S. Defect-Induced Exchange Bias in a Single SrRuO 3 Layer. ACS APPLIED MATERIALS & INTERFACES 2018; 10:27472-27476. [PMID: 30033715 DOI: 10.1021/acsami.8b07918] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Exchange bias stems from the interaction between different magnetic phases, and therefore, it generally occurs in magnetic multilayers. Here, we present a large exchange bias in a single SrRuO3 layer induced by helium ion irradiation. When the fluence increases, the induced defects not only suppress the magnetization and the Curie temperature but also drive a metal-insulator transition at a low temperature. In particular, a large exchange bias field up to ∼0.36 T can be created by the irradiation. This large exchange bias is related to the coexistence of different magnetic and structural phases that are introduced by embedded defects. Our work demonstrates that spintronic properties in complex oxides can be created and enhanced by applying ion irradiation.
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Affiliation(s)
- Changan Wang
- Institute of Ion Beam Physics and Materials Research , Helmholtz-Zentrum Dresden-Rossendorf , Bautzner Landstr. 400 , 01328 Dresden , Germany
- Technische Universität Dresden , D-01062 Dresden , Germany
- Shenzhen Key Laboratory of Laser Engineering, College of Optoelectronic Engineering , Shenzhen University , 518060 Shenzhen , China
| | | | - Ching-Hao Chang
- Leibniz-Institute for Solid State and Materials Research , Helmholtzstrasse 20 , 01069 Dresden , Germany
| | - Hsu-Sheng Tsai
- Institute of Ion Beam Physics and Materials Research , Helmholtz-Zentrum Dresden-Rossendorf , Bautzner Landstr. 400 , 01328 Dresden , Germany
| | - Parul Pandey
- Institute of Ion Beam Physics and Materials Research , Helmholtz-Zentrum Dresden-Rossendorf , Bautzner Landstr. 400 , 01328 Dresden , Germany
| | - Chi Xu
- Institute of Ion Beam Physics and Materials Research , Helmholtz-Zentrum Dresden-Rossendorf , Bautzner Landstr. 400 , 01328 Dresden , Germany
| | - Roman Böttger
- Institute of Ion Beam Physics and Materials Research , Helmholtz-Zentrum Dresden-Rossendorf , Bautzner Landstr. 400 , 01328 Dresden , Germany
| | | | - Yu-Jia Zeng
- Shenzhen Key Laboratory of Laser Engineering, College of Optoelectronic Engineering , Shenzhen University , 518060 Shenzhen , China
| | | | - Manfred Helm
- Institute of Ion Beam Physics and Materials Research , Helmholtz-Zentrum Dresden-Rossendorf , Bautzner Landstr. 400 , 01328 Dresden , Germany
- Technische Universität Dresden , D-01062 Dresden , Germany
| | - Shengqiang Zhou
- Institute of Ion Beam Physics and Materials Research , Helmholtz-Zentrum Dresden-Rossendorf , Bautzner Landstr. 400 , 01328 Dresden , Germany
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11
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Nanoscale Structural Modulation and Low-temperature Magnetic Response in Mixed-layer Aurivillius-type Oxides. Sci Rep 2018; 8:871. [PMID: 29343705 PMCID: PMC5772624 DOI: 10.1038/s41598-018-19448-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 01/02/2018] [Indexed: 12/02/2022] Open
Abstract
Nanoscale structural modulation with different layer numbers in layer-structured complex oxides of the binary Bi4Ti3O12-BiFeO3 system can give rise to intriguing phenomena and extraordinary properties, originating from the correlated interfaces of two different phases with different strain states. In this work, we studied the nanoscale structural modulation induced by Co-substitution in the Aurivillius-type oxide of Bi11Fe3Ti6O33 with a unique and naturally occurred mixed-layer structure. Nanoscale structural evolution via doping occurred from the phase-modulated structure composed of 4- and 5-layer phases to a homogeneous 4-layer structure was clearly observed utilizing x-ray diffraction and electron micro-techniques. Significantly, magnetic response for the samples under various temperatures was recorded and larger magnetic coercive fields (e.g. Hc ∼ 10 kOe at 50 K) were found in the phase-modulated samples. Analyses of the x-ray absorption spectra and magnetic response confirmed that the low-temperature magnetic behaviour should be intrinsic to the phase-modulated structure inside the structural transformation region, mainly arising from structural distortions at the correlated interfaces.
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12
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13
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Autieri C. Antiferromagnetic and xy ferro-orbital order in insulating SrRuO3 thin films with SrO termination. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2016; 28:426004. [PMID: 27588503 DOI: 10.1088/0953-8984/28/42/426004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
By means of first-principles calculations we study the structural, magnetic and electronic properties of SrRuO3 surface for the SrO termination. We find that the RuO6 octahedra and the structure of the SrO layers at the surface are strongly modified as well as the Ru-O-Ru bond angles. We find in the thin films a d xy ferro-orbital order. The d xy orbital becomes the lowest in energy as in other quasitwodimensional ruthenates. Such structural rearrangement, together with a band reduction, leads to a modification of the magnetic properties. We compare the Jahn-Teller effect between the ferromagnetic and antiferromagnetic phases. We show that an insulating G-type antiferromagnetic phase takes place in SrRuO3 thin films, substituting the metallic phase experimentally found in every bulk Sr-ruthenates. The single layer SrRuO3 presents many similarities with the Ca2RuO4 low temperature phase, these similarities disappear with a larger number of layers. A study of the ground state of the as function of the number of layers is presented, the competition between bandwidth and Coulomb repulsion determines the ground state. We propose the disorder as responsible for the exchange bias effect observed.
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Affiliation(s)
- C Autieri
- Department of Physics and Astronomy, Uppsala University, Box-516, 75120 Uppsala, Sweden
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14
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Puggioni D, Giovannetti G, Capone M, Rondinelli JM. Design of a Mott Multiferroic from a Nonmagnetic Polar Metal. PHYSICAL REVIEW LETTERS 2015; 115:087202. [PMID: 26340204 DOI: 10.1103/physrevlett.115.087202] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Indexed: 05/27/2023]
Abstract
We examine the electronic properties of the newly discovered "ferroelectric metal" LiOsO3 combining density-functional and dynamical mean-field theories. We show that the material is close to a Mott transition and that electronic correlations can be tuned to engineer a Mott multiferroic state in the 1/1 superlattice of LiOsO3 and LiNbO3. We use electronic structure calculations to predict that the (LiOsO3)1/(LiNbO3)1 superlattice exhibits strong coupling between magnetic and ferroelectric degrees of freedom with a ferroelectric polarization of 41.2 μC cm(-2), Curie temperature of 927 K, and Néel temperature of 379 K. Our results support a route towards high-temperature multiferroics, i.e., driving nonmagnetic polar metals into correlated insulating magnetic states.
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Affiliation(s)
- Danilo Puggioni
- Department of Materials Science and Engineering, Northwestern University, Illinois 60208-3108, USA
| | - Gianluca Giovannetti
- CNR-IOM-Democritos National Simulation Centre and International School for Advanced Studies (SISSA), I-34136 Trieste, Italy
| | - Massimo Capone
- CNR-IOM-Democritos National Simulation Centre and International School for Advanced Studies (SISSA), I-34136 Trieste, Italy
| | - James M Rondinelli
- Department of Materials Science and Engineering, Northwestern University, Illinois 60208-3108, USA
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15
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Electric field manipulation of magnetic and transport properties in SrRuO3/Pb(Mg1/3Nb2/3)O3-PbTiO3 heterostructure. Sci Rep 2014; 4:6991. [PMID: 25384967 PMCID: PMC4227015 DOI: 10.1038/srep06991] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 10/20/2014] [Indexed: 11/09/2022] Open
Abstract
The electric field manipulation of magnetic properties is currently of great interest for the opportunities provided in low-energy-consuming spintronics devices. Here, we report the effect of electric field on magnetic and transport properties of the ferromagnetic SrRuO(3) film which is epitaxially grown on Pb(Mg(1/3)Nb(2/3))O3-PbTiO(3) ferroelectric substrate. With the application of electric field on the substrate, the magnetization, Curie temperature and resistivity of SrRuO(3) are effectively modified. The mechanism of the electric field manipulation of these properties is ascribed to the rotations of RuO6 oxygen octahedra caused by the electric-field-induced strain, which changes the overlap and hybridization between the Ru 4d orbitals and O 2p orbitals, resulting in the modification of the magnetic and electronic properties.
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16
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Zhai X, Cheng L, Liu Y, Schlepütz CM, Dong S, Li H, Zhang X, Chu S, Zheng L, Zhang J, Zhao A, Hong H, Bhattacharya A, Eckstein JN, Zeng C. Correlating interfacial octahedral rotations with magnetism in (LaMnO3+δ)N/(SrTiO3)N superlattices. Nat Commun 2014; 5:4283. [PMID: 25005724 DOI: 10.1038/ncomms5283] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 06/03/2014] [Indexed: 11/10/2022] Open
Abstract
Lattice distortion due to oxygen octahedral rotations have a significant role in mediating the magnetism in oxides, and recently attracts a lot of interests in the study of complex oxides interface. However, the direct experimental evidence for the interrelation between octahedral rotation and magnetism at interface is scarce. Here we demonstrate that interfacial octahedral rotation are closely linked to the strongly modified ferromagnetism in (LaMnO3+δ)N/(SrTiO3)N superlattices. The maximized ferromagnetic moment in the N=6 superlattice is accompanied by a metastable structure (space group Imcm) featuring minimal octahedral rotations (a(-)a(-)c(-), α~4.2°, γ~0.5°). Quenched ferromagnetism for N<4 superlattices is correlated to a substantially enhanced c axis octahedral rotation (a(-)a(-)c(-), α~3.8°, γ~8° for N=2). Monte-Carlo simulation based on double-exchange model qualitatively reproduces the experimental observation, confirming the correlation between octahedral rotation and magnetism. Our study demonstrates that engineering superlattices with controllable interfacial structures can be a feasible new route in realizing functional magnetic materials.
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Affiliation(s)
- Xiaofang Zhai
- 1] Hefei National Laboratory for Physical Sciences at the Microscale, Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China [2] Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Long Cheng
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Yang Liu
- X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | | | - Shuai Dong
- Department of Physics, Southeast University, Nanjing 211189, China
| | - Hui Li
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Xiaoqiang Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Shengqi Chu
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Lirong Zheng
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Jing Zhang
- Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Aidi Zhao
- 1] Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China [2] Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Hawoong Hong
- X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Anand Bhattacharya
- Materials Science Division and Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - James N Eckstein
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Changgan Zeng
- 1] Hefei National Laboratory for Physical Sciences at the Microscale, Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China [2] Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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Bern F, Ziese M, Setzer A, Pippel E, Hesse D, Vrejoiu I. Structural, magnetic and electrical properties of SrRuO3 films and SrRuO3/SrTiO3 superlattices. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:496003. [PMID: 24184982 DOI: 10.1088/0953-8984/25/49/496003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
SrRuO3 films and SrRuO3/SrTiO3 superlattices grown on SrTiO3(001) were studied by structural, magnetic, magnetoresistance and Hall effect measurements. The superlattices showed heteroepitaxial growth with coherent interfaces and a Ru/Ti diffusion region of 1-1.5 unit cells. The resistivity had metallic character above a critical thickness of 3-4 unit cells, becoming insulating below. There was no hint of conduction processes along the interfaces. Both magnetization and magnetoresistance measurements showed an increase of the magnetic anisotropy, consistent with magnetostriction effects. The magnetostriction coefficient was estimated as λ100 ∼ 1.4 × 10(-4). Three unit cell thick SrRuO3 layers in SrRuO3/SrTiO3 superlattices were found to have tetragonal crystal symmetry, as deduced from the sign change of the anomalous Hall constant.
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Affiliation(s)
- F Bern
- Division of Superconductivity and Magnetism, Faculty of Physics and Geosciences, University of Leipzig, D-04103 Leipzig, Germany
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