1
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Verhage M, van der Minne E, Kiens EM, Korol L, Spiteri RJ, Koster G, Green RJ, Baeumer C, Flipse CFJ. Electronic and Structural Disorder of the Epitaxial La 0.67Sr 0.33MnO 3 Surface. ACS APPLIED MATERIALS & INTERFACES 2024; 16. [PMID: 38619160 PMCID: PMC11056928 DOI: 10.1021/acsami.3c17639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 04/16/2024]
Abstract
Understanding and tuning epitaxial complex oxide films are crucial in controlling the behavior of devices and catalytic processes. Substrate-induced strain, doping, and layer growth are known to influence the electronic and magnetic properties of the bulk of the film. In this study, we demonstrate a clear distinction between the bulk and surface of thin films of La0.67Sr0.33MnO3 in terms of chemical composition, electronic disorder, and surface morphology. We use a combined experimental approach of X-ray-based characterization methods and scanning probe microscopy. Using X-ray diffraction and resonant X-ray reflectivity, we uncover surface nonstoichiometry in the strontium and lanthanum alongside an accumulation of oxygen vacancies. With scanning tunneling microscopy, we observed an electronic phase separation (EPS) on the surface related to this nonstoichiometry. The EPS is likely driving the temperature-dependent resistivity transition and is a cause of proposed mixed-phase ferromagnetic and paramagnetic states near room temperature in these thin films.
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Affiliation(s)
- Michael Verhage
- Molecular
Materials and Nanosystems (M2N)—Department of Applied Physics, Eindhoven University of Technology, Eindhoven 5612 AP, Netherlands
| | - Emma van der Minne
- MESA+
Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, Enschede 7522 NB, Netherlands
| | - Ellen M. Kiens
- MESA+
Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, Enschede 7522 NB, Netherlands
| | - Lucas Korol
- Department
of Physics & Engineering Physics, University
of Saskatchewan, Saskatoon S7N 5A2, Canada
| | - Raymond J. Spiteri
- Department
of Computer Science, University of Saskatchewan, Saskatoon S7N 5A2, Canada
| | - Gertjan Koster
- MESA+
Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, Enschede 7522 NB, Netherlands
| | - Robert J. Green
- Department
of Physics & Engineering Physics, University
of Saskatchewan, Saskatoon S7N 5A2, Canada
- Stewart
Blusson Quantum Matter Institute, University
of British Columbia, Vancouver V6T 1Z4, Canada
| | - Christoph Baeumer
- MESA+
Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, Enschede 7522 NB, Netherlands
- Peter
Gruenberg
Institute and JARA-FIT, Forschungszentrum
Juelich GmbH, Juelich 52428, Germany
| | - Cornelis F. J. Flipse
- Molecular
Materials and Nanosystems (M2N)—Department of Applied Physics, Eindhoven University of Technology, Eindhoven 5612 AP, Netherlands
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2
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Mattiat H, Schneider L, Reiser P, Poggio M, Sahafi P, Jordan A, Budakian R, Averyanov DV, Sokolov IS, Taldenkov AN, Parfenov OE, Kondratev OA, Tokmachev AM, Storchak VG. Mapping the phase-separated state in a 2D magnet. NANOSCALE 2024; 16:5302-5312. [PMID: 38372414 DOI: 10.1039/d3nr06550b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Intrinsic 2D magnets have recently been established as a playground for studies on fundamentals of magnetism, quantum phases, and spintronic applications. The inherent instability at low dimensionality often results in coexistence and/or competition of different magnetic orders. Such instability of magnetic ordering may manifest itself as phase-separated states. In 4f 2D materials, magnetic phase separation is expressed in various experiments; however, the experimental evidence is circumstantial. Here, we employ a high-sensitivity MFM technique to probe the spatial distribution of magnetic states in the paradigmatic 4f 2D ferromagnet EuGe2. Below the ferromagnetic transition temperature, we discover the phase-separated state and follow its evolution with temperature and magnetic field. The characteristic length-scale of magnetic domains amounts to hundreds of nanometers. These observations strongly shape our understanding of the magnetic states in 2D materials at the monolayer limit and contribute to engineering of ultra-compact spintronics.
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Affiliation(s)
- Hinrich Mattiat
- Department of Physics & Swiss Nanoscience Institute, University of Basel, 4056 Basel, Switzerland.
| | - Lukas Schneider
- Department of Physics & Swiss Nanoscience Institute, University of Basel, 4056 Basel, Switzerland.
| | - Patrick Reiser
- Department of Physics & Swiss Nanoscience Institute, University of Basel, 4056 Basel, Switzerland.
| | - Martino Poggio
- Department of Physics & Swiss Nanoscience Institute, University of Basel, 4056 Basel, Switzerland.
| | - Pardis Sahafi
- Department of Physics and Astronomy & Institute for Quantum Computing, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Andrew Jordan
- Department of Physics and Astronomy & Institute for Quantum Computing, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Raffi Budakian
- Department of Physics and Astronomy & Institute for Quantum Computing, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Dmitry V Averyanov
- National Research Center "Kurchatov Institute", Kurchatov Sq. 1, 123182 Moscow, Russia.
| | - Ivan S Sokolov
- National Research Center "Kurchatov Institute", Kurchatov Sq. 1, 123182 Moscow, Russia.
| | - Alexander N Taldenkov
- National Research Center "Kurchatov Institute", Kurchatov Sq. 1, 123182 Moscow, Russia.
| | - Oleg E Parfenov
- National Research Center "Kurchatov Institute", Kurchatov Sq. 1, 123182 Moscow, Russia.
| | - Oleg A Kondratev
- National Research Center "Kurchatov Institute", Kurchatov Sq. 1, 123182 Moscow, Russia.
| | - Andrey M Tokmachev
- National Research Center "Kurchatov Institute", Kurchatov Sq. 1, 123182 Moscow, Russia.
| | - Vyacheslav G Storchak
- National Research Center "Kurchatov Institute", Kurchatov Sq. 1, 123182 Moscow, Russia.
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3
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Wang Z, Dong S. Alterferroicity with seesaw-type magnetoelectricity. Proc Natl Acad Sci U S A 2023; 120:e2305197120. [PMID: 38015837 PMCID: PMC10710059 DOI: 10.1073/pnas.2305197120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 10/10/2023] [Indexed: 11/30/2023] Open
Abstract
Primary ferroicities like ferroelectricity and ferromagnetism are essential physical properties of matter. Multiferroics, with coexisting multiple ferroic orders in a single phase, provide a convenient route to magnetoelectricity. Even so, the general trade-off between magnetism and polarity remains inevitable, which prevents practicable magnetoelectric cross-control in the multiferroic framework. Here, an alternative strategy, i.e., the so-called alterferroicity, is proposed to circumvent the magnetoelectric exclusiveness, which exhibits multiple but noncoexisting ferroic orders. The natural exclusion between magnetism and polarity, as an insurmountable weakness of multiferroicity, becomes a distinct advantage in alterferroicity, making it an inborn rich ore for intrinsic strong magnetoelectricity. The general design rules for alterferroic materials rely on the competition between the instabilities of phononic and electronic structures in covalent systems. Based on primary density functional theory calculations, Ti-based trichalcogenides are predicted to be alterferroic candidates, which exhibit unique seesaw-type magnetoelectricity. This alterferroicity, as an emerging branch of the ferroic family, reshapes the framework of magnetoelectricity, going beyond the established scenario based on multiferroicity.
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Affiliation(s)
- Ziwen Wang
- School of Physics, Southeast University, Nanjing211189, China
| | - Shuai Dong
- School of Physics, Southeast University, Nanjing211189, China
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4
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Zhang B, Yang P, Ding J, Chen J, Chow GM. Anisotropic Melting Path of Charge-Ordering Insulator in LSMO/STO Superlattice. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2203933. [PMID: 36461732 PMCID: PMC9896059 DOI: 10.1002/advs.202203933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 10/17/2022] [Indexed: 06/17/2023]
Abstract
Multiple phases coexist in manganite with simultaneously active couplings, and the transition among them depends on the relative intensities of different interactions. However, the melting path with variable intensities is unclear. The concentration and the ordering of oxygen vacancy in previous work are found to induce ferromagnetic charge-ordering insulator phase in [(La0.7 Sr0.3 MnO3 )10 /(SrTiO3 )5 ]n superlattice, which translates into metallic phase with magnetic field H and temperature T. In the current work, the H-T phase diagram for current I//[100] and I//[110] shows a large difference with H normal to the film plane, which is ascribed to the response of a variable range of hopping process to H with the in-plane anisotropic hopping probability of charge carrier. With H rotating from the out-of-plane to the in-plane direction, the preferred occupancy of the3 d z 2 - r 2 $3{d}_{{z}^2 - {r}^2}$ orbital causes a decrease of spin-orbital coupling and lowers the activation energy, inducing a gentler melting process of a charge-ordering insulator. This work shows that the melting path of a charge-ordering insulator phase can be largely modulated in manganite with anisotropy.
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Affiliation(s)
- Bangmin Zhang
- Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesCentre for Physical Mechanics and BiophysicsSchool of PhysicsSun Yat‐sen UniversityGuangzhou510275China
| | - Ping Yang
- Singapore Synchrotron Light Source (SSLS)National University of Singapore5 Research LinkSingapore117603Singapore
| | - Jun Ding
- Department of Materials Science & EngineeringNational University of Singapore9 Engineering Drive 1Singapore117576Singapore
| | - Jingsheng Chen
- Department of Materials Science & EngineeringNational University of Singapore9 Engineering Drive 1Singapore117576Singapore
| | - Gan Moog Chow
- Department of Materials Science & EngineeringNational University of Singapore9 Engineering Drive 1Singapore117576Singapore
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5
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Li Q, Miao T, Zhang H, Lin W, He W, Zhong Y, Xiang L, Deng L, Ye B, Shi Q, Zhu Y, Guo H, Wang W, Zheng C, Yin L, Zhou X, Xiang H, Shen J. Electronically phase separated nano-network in antiferromagnetic insulating LaMnO 3/PrMnO 3/CaMnO 3 tricolor superlattice. Nat Commun 2022; 13:6593. [PMID: 36329034 PMCID: PMC9633694 DOI: 10.1038/s41467-022-34377-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 10/21/2022] [Indexed: 11/06/2022] Open
Abstract
Strongly correlated materials often exhibit an electronic phase separation (EPS) phenomena whose domain pattern is random in nature. The ability to control the spatial arrangement of the electronic phases at microscopic scales is highly desirable for tailoring their macroscopic properties and/or designing novel electronic devices. Here we report the formation of EPS nanoscale network in a mono-atomically stacked LaMnO3/CaMnO3/PrMnO3 superlattice grown on SrTiO3 (STO) (001) substrate, which is known to have an antiferromagnetic (AFM) insulating ground state. The EPS nano-network is a consequence of an internal strain relaxation triggered by the structural domain formation of the underlying STO substrate at low temperatures. The same nanoscale network pattern can be reproduced upon temperature cycling allowing us to employ different local imaging techniques to directly compare the magnetic and transport state of a single EPS domain. Our results confirm the one-to-one correspondence between ferromagnetic (AFM) to metallic (insulating) state in manganite. It also represents a significant step in a paradigm shift from passively characterizing EPS in strongly correlated systems to actively engaging in its manipulation.
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Affiliation(s)
- Qiang Li
- State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai, 200433, China
- Department of Physics, Fudan University, Shanghai, 200433, China
| | - Tian Miao
- Department of Physics, Fudan University, Shanghai, 200433, China
- School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an, Shanxi, 710049, China
| | - Huimin Zhang
- Department of Physics, Fudan University, Shanghai, 200433, China
- Key Laboratory of Computational Physical Sciences (Ministry of Education) and Institute of Computational Physical Sciences, Fudan University, Shanghai, 200433, China
- Shanghai Qi Zhi Institute, Shanghai, 200232, China
| | - Weiyan Lin
- State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai, 200433, China
| | - Wenhao He
- State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai, 200433, China
- Department of Physics, Fudan University, Shanghai, 200433, China
| | - Yang Zhong
- Department of Physics, Fudan University, Shanghai, 200433, China
- Key Laboratory of Computational Physical Sciences (Ministry of Education) and Institute of Computational Physical Sciences, Fudan University, Shanghai, 200433, China
- Shanghai Qi Zhi Institute, Shanghai, 200232, China
| | - Lifen Xiang
- Department of Physics, Fudan University, Shanghai, 200433, China
| | - Lina Deng
- Department of Physics, Fudan University, Shanghai, 200433, China
| | - Biying Ye
- Department of Physics, Fudan University, Shanghai, 200433, China
| | - Qian Shi
- Department of Physics, Fudan University, Shanghai, 200433, China
| | - Yinyan Zhu
- State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai, 200433, China
- Shanghai Qi Zhi Institute, Shanghai, 200232, China
- Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai, 201210, China
| | - Hangwen Guo
- State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai, 200433, China
- Shanghai Qi Zhi Institute, Shanghai, 200232, China
- Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai, 201210, China
| | - Wenbin Wang
- State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai, 200433, China
- Shanghai Qi Zhi Institute, Shanghai, 200232, China
- Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai, 201210, China
| | - Changlin Zheng
- State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai, 200433, China
- Department of Physics, Fudan University, Shanghai, 200433, China
| | - Lifeng Yin
- State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai, 200433, China
- Department of Physics, Fudan University, Shanghai, 200433, China
- Shanghai Qi Zhi Institute, Shanghai, 200232, China
- Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai, 201210, China
- Shanghai Research Center for Quantum Sciences, Shanghai, 201315, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, China
| | - Xiaodong Zhou
- State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai, 200433, China.
- Shanghai Qi Zhi Institute, Shanghai, 200232, China.
- Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai, 201210, China.
| | - Hongjun Xiang
- Department of Physics, Fudan University, Shanghai, 200433, China.
- Key Laboratory of Computational Physical Sciences (Ministry of Education) and Institute of Computational Physical Sciences, Fudan University, Shanghai, 200433, China.
- Shanghai Qi Zhi Institute, Shanghai, 200232, China.
| | - Jian Shen
- State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing, Fudan University, Shanghai, 200433, China.
- Department of Physics, Fudan University, Shanghai, 200433, China.
- Shanghai Qi Zhi Institute, Shanghai, 200232, China.
- Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai, 201210, China.
- Shanghai Research Center for Quantum Sciences, Shanghai, 201315, China.
- Collaborative Innovation Center of Advanced Microstructures, Nanjing, 210093, China.
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6
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Zhang Z, Shao J, Jin F, Dai K, Li J, Lan D, Hua E, Han Y, Wei L, Cheng F, Ge B, Wang L, Zhao Y, Wu W. Uniaxial Strain and Hydrostatic Pressure Engineering of the Hidden Magnetism in La 1-xCa xMnO 3 (0 ≤ x ≤ 1/2) Thin Films. NANO LETTERS 2022; 22:7328-7335. [PMID: 36067249 DOI: 10.1021/acs.nanolett.2c01352] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Here, using various substrates, we demonstrate that the in-plane uniaxial strain engineering can enhance the Jahn-Teller distortions and promote selective orbital occupancy to induce an emergent antiferromagnetic insulating (AFI) phase at x = 1/3 of La1-xCaxMnO3. Such an AFI phase depends not only on the magnitude of epitaxial strain but also on the symmetry of the substrates. Using the large uniaxial strain imparted by DyScO3(001) substrate, the AFI ground state is achieved in a wide range of doping levels (0 ≤ x ≤ 1/2), leaving an extended AFI phase diagram. Moreover, it is found that hydrostatic pressure can tune the AFI phase back to a hidden ferromagnetic metallic phase, accompanied by the formation of accommodation strain. The coaction of the accommodation strain, uniaxial strain, and hydrostatic pressure produces complex phase competition and evolution, and the result may shed light on phase space control of other functional perovskites with the competing magnetic interactions.
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Affiliation(s)
- Zixun Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Jifeng Shao
- Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- International Quantum Academy, Shenzhen 518048, China
| | - Feng Jin
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Kunjie Dai
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Jingyuan Li
- Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
| | - Da Lan
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Enda Hua
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Yuyan Han
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
| | - Long Wei
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China
| | - Feng Cheng
- Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
| | - Binghui Ge
- Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
| | - Lingfei Wang
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Yue Zhao
- Shenzhen Institute for Quantum Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China
- Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China
| | - Wenbin Wu
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
- Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
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7
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Simpson S, Milton M, Fop S, Stenning GBG, Hopper HA, Ritter C, Mclaughlin AC. Localized Spin Dimers and Structural Distortions in the Hexagonal Perovskite Ba 3CaMo 2O 9. Inorg Chem 2022; 61:11622-11628. [PMID: 35852971 PMCID: PMC9377418 DOI: 10.1021/acs.inorgchem.2c01102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Indexed: 11/29/2022]
Abstract
Extended solid-state materials based on the hexagonal perovskite framework are typified by close competition between localized magnetic interactions and quasi-molecular electronic states. Here, we report the structural and magnetic properties of the new six-layer hexagonal perovskite Ba3CaMo2O9. Neutron diffraction experiments, combined with magnetic susceptibility measurements, show that the Mo2O9 dimers retain localized character down to 5 K and adopt nonmagnetic spin-singlet ground states. This is in contrast to the recently reported Ba3SrMo2O9 analogue, in which the Mo2O9 dimers spontaneously separate into a mixture of localized and quasi-molecular ground states. Structural distortions in both Ba3CaMo2O9 and Ba3SrMo2O9 have been studied with the aid of distortion mode analyses to elucidate the coupling between the crystal lattice and electronic interactions in 6H Mo5+ hexagonal perovskites.
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Affiliation(s)
- Struan Simpson
- Chemistry
Department, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, U.K.
| | - Michael Milton
- Chemistry
Department, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, U.K.
| | - Sacha Fop
- Chemistry
Department, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, U.K.
| | - Gavin B. G. Stenning
- ISIS
Experimental Operations Division, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot OX11 0QX, U.K.
| | | | - Clemens Ritter
- Institut
Laue Langevin, 71 Avenue
des Martyrs, F-38042 Grenoble Cedex 9, France
| | - Abbie C. Mclaughlin
- Chemistry
Department, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, U.K.
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8
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Li Q, Ren Y, Zhang Q, Gu L, Huang Q, Wu H, Sun J, Cao Y, Lin K, Xing X. Chemical order-disorder nanodomains in Fe 3Pt bulk alloy. Natl Sci Rev 2022; 9:nwac053. [PMID: 36778106 PMCID: PMC9905646 DOI: 10.1093/nsr/nwac053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 12/07/2021] [Accepted: 03/16/2022] [Indexed: 11/13/2022] Open
Abstract
Chemical ordering is a common phenomenon and highly correlated with the properties of solid materials. By means of the redistribution of atoms and chemical bonds, it invokes an effective lattice adjustment and tailors corresponding physical properties. To date, however, directly probing the 3D interfacial interactions of chemical ordering remains a big challenge. In this work, we deciphered the interlaced distribution of nanosized domains with chemical order/disorder in Fe3Pt bulk alloy. HAADF-STEM images evidence the existence of such nanodomains. The reverse Monte Carlo method with the X-ray pair distribution function data reveal the 3D distribution of local structures and the tensile effect in the disordered domains at the single-atomic level. The chemical bonding around the domain boundary changes the bonding feature in the disordered side and reduces the local magnetic moment of Fe atoms. This results in a suppressed negative thermal expansion and extended temperature range in Fe3Pt bulk alloy with nanodomains. Our study demonstrates a local revelation for the chemical order/disorder nanodomains in bulk alloy. The understanding gained from atomic short-range interactions within the domain boundaries provides useful insights with regard to designing new functional compounds.
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Affiliation(s)
- Qiang Li
- Beijing Advanced Innovation Center for Materials Genome Engineering, Institute of Solid State Chemistry, University of Science and Technology Beijing, Beijing 100083, China
| | - Yang Ren
- X-Ray Science Division, Argonne National Laboratory, Argonne, IL 60439, USA
| | - Qinghua Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Lin Gu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Qingzhen Huang
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899-6102, USA
| | - Hui Wu
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899-6102, USA
| | - Jing Sun
- Beijing Advanced Innovation Center for Materials Genome Engineering, Institute of Solid State Chemistry, University of Science and Technology Beijing, Beijing 100083, China
| | - Yili Cao
- Beijing Advanced Innovation Center for Materials Genome Engineering, Institute of Solid State Chemistry, University of Science and Technology Beijing, Beijing 100083, China
| | - Kun Lin
- Beijing Advanced Innovation Center for Materials Genome Engineering, Institute of Solid State Chemistry, University of Science and Technology Beijing, Beijing 100083, China
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9
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Ye B, Miao T, Zhu Y, Huang H, Yang Y, Shuai M, Zhu Z, Guo H, Wang W, Zhu Y, Yin L, Shen J. Pulsed laser deposition of large-sized superlattice films with high uniformity. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:113906. [PMID: 34852506 DOI: 10.1063/5.0068795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 10/21/2021] [Indexed: 06/13/2023]
Abstract
Oxide superlattices often exhibit emergent physical properties that are desirable for future information device applications. The most common growth technique for fabrication of oxide superlattices is pulsed laser deposition (PLD), which is convenient yet powerful for the growth of various oxide superlattices. However, the sample size prepared by PLD is rather small confined by the plasmon plume, which greatly limits its potential for device applications. Here, we design a PLD system that is capable of fabricating large-sized oxide superlattices with high uniformity. Specifically, during growth, the laser beam scans the target surface by combining the pitch and yaw angle rotation of the high reflective mirror and the linear motion of the focus lens. A SiC susceptor is placed in between the sample holder and the substrate to improve the large area infrared heating efficiency. Using such a system, droplet-free 10 × 10 mm2 [(LSMO)12/(PCMO)6]7 superlattices are epitaxially grown with the same period of superlattices across the whole sample areas. The high uniformity of the superlattices is further illustrated by near identical physical properties of all regions of the superlattice films. The present PLD system can be used to grow various kinds of oxide superlattices with the area size as large as 2 in., which is highly useful for device applications of oxides.
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Affiliation(s)
- Biying Ye
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Tian Miao
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Yi Zhu
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Haiming Huang
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Yulong Yang
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Mingming Shuai
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Zhifei Zhu
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Hangwen Guo
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Wenbin Wang
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Yinyan Zhu
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Lifeng Yin
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Jian Shen
- State Key Laboratory of Surface Physics and Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
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10
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Direct experimental evidence of physical origin of electronic phase separation in manganites. Proc Natl Acad Sci U S A 2020; 117:7090-7094. [PMID: 32179681 DOI: 10.1073/pnas.1920502117] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Electronic phase separation in complex oxides is the inhomogeneous spatial distribution of electronic phases, involving length scales much larger than those of structural defects or nonuniform distribution of chemical dopants. While experimental efforts focused on phase separation and established its correlation with nonlinear responses under external stimuli, it remains controversial whether phase separation requires quenched disorder for its realization. Early theory predicted that if perfectly "clean" samples could be grown, both phase separation and nonlinearities would be replaced by a bicritical-like phase diagram. Here, using a layer-by-layer superlattice growth technique we fabricate a fully chemically ordered "tricolor" manganite superlattice, and compare its properties with those of isovalent alloyed manganite films. Remarkably, the fully ordered manganite does not exhibit phase separation, while its presence is pronounced in the alloy. This suggests that chemical-doping-induced disorder is crucial to stabilize the potentially useful nonlinear responses of manganites, as theory predicted.
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11
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Song SK, Samad A, Wippermann S, Yeom HW. Dynamical Metal to Charge-Density-Wave Junctions in an Atomic Wire Array. NANO LETTERS 2019; 19:5769-5773. [PMID: 31276408 DOI: 10.1021/acs.nanolett.9b02438] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We investigated the atomic scale electronic phase separation emerging from a quasi-1D charge-density-wave (CDW) state of the In atomic wire array on a Si(111) surface. Spatial variations of the CDW gap and amplitude are quantified for various interfaces of metallic and insulating CDW domains by scanning tunneling microscopy and spectroscopy (STS). The strong anisotropy in the metal-insulator junctions is revealed with an order of magnitude difference in the interwire and intrawire junction lengths of 0.4 and 7 nm, respectively. The intrawire junction length is reduced dramatically by an atomic scale impurity, indicating the tunability of the metal-insulator junction in an atomic scale. Density functional theory calculations disclose the dynamical nature of the intrawire junction formation and tunability.
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Affiliation(s)
- Sun Kyu Song
- Center for Artificial Low Dimensional Electronic Systems , Institute for Basic Science (IBS) , Pohang 37673 , Republic of Korea
- Department of Physics , Pohang University of Science and Technology (POSTECH) , Pohang 37673 , Republic of Korea
| | - Abdus Samad
- Max-Planck-Institut für Eisenforschung GmbH , Düsseldorf 40237 , Germany
| | - Stefan Wippermann
- Max-Planck-Institut für Eisenforschung GmbH , Düsseldorf 40237 , Germany
| | - Han Woong Yeom
- Center for Artificial Low Dimensional Electronic Systems , Institute for Basic Science (IBS) , Pohang 37673 , Republic of Korea
- Department of Physics , Pohang University of Science and Technology (POSTECH) , Pohang 37673 , Republic of Korea
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12
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Abstract
Incomplete transformations from ferromagnetic to charge ordered states in manganite perovskites lead to phase-separated microstructures showing colossal magnetoresistances. However, it is unclear whether electronic matter can show spontaneous separation into multiple phases distinct from the high temperature state. Here we show that paramagnetic CaFe3O5 undergoes separation into two phases with different electronic and spin orders below their joint magnetic transition at 302 K. One phase is charge, orbital and trimeron ordered similar to the ground state of magnetite, Fe3O4, while the other has Fe2+/Fe3+charge averaging. Lattice symmetry is unchanged but differing strains from the electronic orders probably drive the phase separation. Complex low symmetry materials like CaFe3O5 where charge can be redistributed between distinct cation sites offer possibilities for the generation and control of electronic phase separated nanostructures. Electronic phase separation is an important feature of many correlated perovskite compounds but hasn’t been seen in other complex oxides with similar physical behaviour such as magnetite. Hong et al. find phase separation between a magnetite-like charge ordered phase and a charge averaged phase in CaFe3O5.
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Lin H, Liu H, Lin L, Dong S, Chen H, Bai Y, Miao T, Yu Y, Yu W, Tang J, Zhu Y, Kou Y, Niu J, Cheng Z, Xiao J, Wang W, Dagotto E, Yin L, Shen J. Unexpected Intermediate State Photoinduced in the Metal-Insulator Transition of Submicrometer Phase-Separated Manganites. PHYSICAL REVIEW LETTERS 2018; 120:267202. [PMID: 30004745 DOI: 10.1103/physrevlett.120.267202] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 05/09/2018] [Indexed: 06/08/2023]
Abstract
At ultrafast timescales, the initial and final states of a first-order metal-insulator transition often coexist forming clusters of the two phases. Here, we report an unexpected third long-lived intermediate state emerging at the photoinduced first-order metal-insulator transition of La_{0.325}Pr_{0.3}Ca_{0.375}MnO_{3}, known to display submicrometer length-scale phase separation. Using magnetic force microscopy and time-dependent magneto-optical Kerr effect, we determined that the third state is a nanoscale mixture of the competing ferromagnetic metallic and charge-ordered insulating phases, with its own physical properties. This discovery bridges the two different families of colossal magnetoresistant manganites known experimentally and shows for the first time that the associated states predicted by theory can coexist in a single sample.
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Affiliation(s)
- Hanxuan Lin
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Hao Liu
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Lingfang Lin
- School of Physics, Southeast University, Nanjing 211189, China
| | - Shuai Dong
- School of Physics, Southeast University, Nanjing 211189, China
| | - Hongyan Chen
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Yu Bai
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Tian Miao
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Yang Yu
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Weichao Yu
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Jing Tang
- Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Yinyan Zhu
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Yunfang Kou
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Jiebin Niu
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
| | - Zhaohua Cheng
- Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Jiang Xiao
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
- Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
| | - Wenbin Wang
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
- Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
| | - Elbio Dagotto
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Lifeng Yin
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
- Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
| | - Jian Shen
- State Key Laboratory of Surface Physics and Department of Physics, Fudan University, Shanghai 200433, China
- Institute for Nanoelectronics Devices and Quantum Computing, Fudan University, Shanghai 200433, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
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14
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Jeon J, Jung J, Chow KH. Electron beam induced tunneling magnetoresistance in spatially confined manganite bridges. NANOSCALE 2017; 9:19304-19309. [PMID: 29192923 DOI: 10.1039/c7nr04232a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Certain manganites exhibit rich and technologically relevant transport properties which can often be attributed to the existence and changes of the intrinsic electronic phase competition within these materials. Here we demonstrate that a scanning electron beam can be used to artificially create domain configurations within La0.3Pr0.4Ca0.3MnO3 thin film microbridges that results in novel magneto-transport effects. In particular, the electron beam preferentially produces insulating regions within the narrow film and can be used to create a configuration consisting of ferromagnetic metallic domains separated by a potential barrier. This arrangement enables the spin-dependent tunneling of charge carriers and can produce large switching tunneling magnetoresistance effects which were initially absent. Hence, this work describes a new and potentially powerful method for engineering the electronic phase domains in manganites to generate functional transport properties that are important for spintronic devices.
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Affiliation(s)
- J Jeon
- Department of Physics, University of Alberta, Edmonton T6G 2E1, Canada.
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15
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Thi N'Goc HL, Mouafo LDN, Etrillard C, Torres-Pardo A, Dayen JF, Rano S, Rousse G, Laberty-Robert C, Calbet JG, Drillon M, Sanchez C, Doudin B, Portehault D. Surface-Driven Magnetotransport in Perovskite Nanocrystals. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1604745. [PMID: 28009460 DOI: 10.1002/adma.201604745] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2016] [Revised: 11/19/2016] [Indexed: 06/06/2023]
Abstract
Unique insights into magnetotransport in 20 nm ligand-free La0.67 Sr0.33 MnO3 perovskite nanocrystals of nearly perfect crystalline quality reveal a chemically altered 0.8 nm thick surface layer that triggers exceptionally large magnetoresistance at low temperature, independently of the spin polarization of the ferromagnetic core. This discovery shows how the nanoscale impacts magnetotransport in a material widely spread as electrode in hybrid spintronic devices.
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Affiliation(s)
- Ha Le Thi N'Goc
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, Laboratoire de Chimie de la Matière Condensée de Paris (CMCP), 11 place Marcelin Berthelot, F-75005, Paris, France
| | - Louis Donald Notemgnou Mouafo
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, 23 rue du Loess, BP 43, F-67034, Strasbourg, France
| | - Céline Etrillard
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, 23 rue du Loess, BP 43, F-67034, Strasbourg, France
| | - Almudena Torres-Pardo
- Departamento de Química Inorgánica I, Facultad de Químicas, Universidad Complutense CEI Moncloa, 28040, Madrid, Spain
| | - Jean-François Dayen
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, 23 rue du Loess, BP 43, F-67034, Strasbourg, France
| | - Simon Rano
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, Laboratoire de Chimie de la Matière Condensée de Paris (CMCP), 11 place Marcelin Berthelot, F-75005, Paris, France
| | - Gwenaëlle Rousse
- Sorbonne Universités, UPMC Univ Paris 06, Chimie du Solide et de l'Energie, UMR 8260, Collège de France, 11 place Marcelin Berthelot, 75231, Paris Cedex 05, France
| | - Christel Laberty-Robert
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, Laboratoire de Chimie de la Matière Condensée de Paris (CMCP), 11 place Marcelin Berthelot, F-75005, Paris, France
| | - Jose Gonzales Calbet
- Departamento de Química Inorgánica I, Facultad de Químicas, Universidad Complutense CEI Moncloa, 28040, Madrid, Spain
- Centro Nacional de Microscopía Electrónica, Universidad Complutense, 28040, Madrid, Spain
| | - Marc Drillon
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, 23 rue du Loess, BP 43, F-67034, Strasbourg, France
| | - Clément Sanchez
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, Laboratoire de Chimie de la Matière Condensée de Paris (CMCP), 11 place Marcelin Berthelot, F-75005, Paris, France
| | - Bernard Doudin
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, 23 rue du Loess, BP 43, F-67034, Strasbourg, France
| | - David Portehault
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, Laboratoire de Chimie de la Matière Condensée de Paris (CMCP), 11 place Marcelin Berthelot, F-75005, Paris, France
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16
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Chen L, Fan J, Tong W, Hu D, Ji Y, Liu J, Zhang L, Pi L, Zhang Y, Yang H. Evolution of the intrinsic electronic phase separation in La 0.6Er 0.1Sr 0.3MnO 3 perovskite. Sci Rep 2016; 6:14. [PMID: 28442764 PMCID: PMC5431341 DOI: 10.1038/s41598-016-0009-0] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 08/15/2016] [Indexed: 11/19/2022] Open
Abstract
Magnetic and electronic transport properties of perovskite manganite La0.6Er0.1Sr0.3MnO3 have been thoroughly examined through the measurements of magnetization, electron paramagnetic resonance(EPR), and resistivity. It was found that the substitution of Er3+ for La3+ ions introduced the chemical disorder and additional strain in this sample. An extra resonance signal occurred in EPR spectra at high temperatures well above TC gives a strong evidence of electronic phase separation(EPS). The analysis of resistivity enable us to identify the polaronic transport mechanism in the paramagnetic region. At low temperature, a new ferromagnetic interaction generates in the microdomains of Er3+-disorder causing the second increase of magnetization. However, the new ferromagnetic interaction does not improve but decreases electronic transport due to the enhancement of interface resistance among neighboring domains. In view of a really wide temperature region for the EPS existence, this sample provides an ideal platform to uncover the evolution law of different magnetic structures in perovskite manganites.
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Affiliation(s)
- Lili Chen
- Department of Applied Physics, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China
| | - Jiyu Fan
- Department of Applied Physics, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China.
| | - Wei Tong
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Dazhi Hu
- Department of Applied Physics, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China
| | - Yanda Ji
- Department of Applied Physics, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China
| | - Jindong Liu
- Department of Applied Physics, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China
| | - Lei Zhang
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Li Pi
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Yuheng Zhang
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei, 230031, China
| | - Hao Yang
- Department of Applied Physics, Nanjing University of Aeronautics and Astronautics, Nanjing, 210016, China.
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17
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Abstract
In complex oxides systems such as manganites, electronic phase separation (EPS), a consequence of strong electronic correlations, dictates the exotic electrical and magnetic properties of these materials. A fundamental yet unresolved issue is how EPS responds to spatial confinement; will EPS just scale with size of an object, or will the one of the phases be pinned? Understanding this behavior is critical for future oxides electronics and spintronics because scaling down of the system is unavoidable for these applications. In this work, we use La0.325Pr0.3Ca0.375MnO3 (LPCMO) single crystalline disks to study the effect of spatial confinement on EPS. The EPS state featuring coexistence of ferromagnetic metallic and charge order insulating phases appears to be the low-temperature ground state in bulk, thin films, and large disks, a previously unidentified ground state (i.e., a single ferromagnetic phase state emerges in smaller disks). The critical size is between 500 nm and 800 nm, which is similar to the characteristic length scale of EPS in the LPCMO system. The ability to create a pure ferromagnetic phase in manganite nanodisks is highly desirable for spintronic applications.
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