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Zheng J, Shi W, Li Z, Zhang J, Yang CY, Zhu Z, Wang M, Zhang J, Han F, Zhang H, Chen Y, Hu F, Shen B, Chen Y, Sun J. Charge-Transfer-Induced Interfacial Ferromagnetism in Ferromagnet-Free Oxide Heterostructures. ACS NANO 2024; 18:9232-9241. [PMID: 38466082 DOI: 10.1021/acsnano.4c01910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Due to the strong interlayer coupling between multiple degrees of freedom, oxide heterostructures have demonstrated exotic properties that are not shown by their bulk counterparts. One of the most interesting properties is ferromagnetism at the interface formed between "nonferromagnetic" compounds. Here we report on the interfacial ferromagnetic phase induced in the superlattices consisting of the two paramagnetic oxides CaRuO3 (CRO) and LaNiO3 (LNO). By varying the sublayer thickness in the superlattice period, we demonstrate that the ferromagnetic order has been established in both CaRuO3 and LaNiO3 sublayers, exhibiting an identical Curie temperature of ∼75 K. The X-ray absorption spectra suggest a strong charge transfer from Ru to Ni at the interface, triggering superexchange interactions between Ru/Ni ions and giving rise to the emergent ferromagnetic phase. Moreover, the X-ray linear dichroism spectra reveal the preferential occupancy of the d3z2-r2 orbital for the Ru ions and the dx2-y2 orbital for the Ni ions in the heterostructure. This leads to different magnetic anisotropy of the superlattices when they are dominated by CRO or LNO sublayers. This work clearly demonstrates a charge-transfer-induced interfacial ferromagnetic phase in the whole ferromagnet-free oxide heterostructures, offering a feasible way to tailor oxide materials for desired functionalities.
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Affiliation(s)
- Jie Zheng
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Wenxiao Shi
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Zhe Li
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Jing Zhang
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China
| | - Chao-Yao Yang
- Department of Materials Science and Engineering, National Yang Ming Chiao Tung University, Hsinchu 300, Taiwan
| | - Zhaozhao Zhu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Mengqin Wang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Jine Zhang
- School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, People's Republic of China
| | - Furong Han
- School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, People's Republic of China
| | - Hui Zhang
- School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, People's Republic of China
| | - Yunzhong Chen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Fengxia Hu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Baogen Shen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, People's Republic of China
| | - Yuansha Chen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Jirong Sun
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Spintronics Institute, School of Physics and Technology, University of Jinan, Jinan 250022, China
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2
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Wang M, Zhu T, Bai H, Yin Z, Xu H, Shi W, Li Z, Zheng J, Gan Y, Chen Y, Shen B, Chen Y, Zhang Q, Hu F, Sun JR. Layered Ferromagnetic Structure Caused by the Proximity Effect and Interlayer Charge Transfer for LaNiO 3/LaMnO 3 Superlattices. NANO LETTERS 2024; 24:1122-1129. [PMID: 38230636 DOI: 10.1021/acs.nanolett.3c03658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Magnetic proximity-induced magnetism in paramagnetic LaNiO3 (LNO) has spurred intensive investigations in the past decade. However, no consensus has been reached so far regarding the magnetic order in LNO layers in relevant heterostructures. This paper reports a layered ferromagnetic structure for the (111)-oriented LNO/LaMnO3 (LMO) superlattices. It is found that each period of the superlattice consisted of an insulating LNO-interfacial phase (five unit cells in thickness, ∼1.1 nm), a metallic LNO-inner phase, a poorly conductive LMO-interfacial phase (three unit cells in thickness, ∼0.7 nm), and an insulating LMO-inner phase. All four of these phases are ferromagnetic, showing different magnetizations. The Mn-to-Ni interlayer charge transfer is responsible for the emergence of a layered magnetic structure, which may cause magnetic interaction across the LNO/LMO interface and double exchange within the LMO-interfacial layer. This work indicates that the proximity effect is an effective means of manipulating the magnetic state and associated properties of complex oxides.
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Affiliation(s)
- Mengqin Wang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tao Zhu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Spallation Neutron Source Science Center, Dongguan 523803, China
| | - He Bai
- Spallation Neutron Source Science Center, Dongguan 523803, China
- Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Zhuo Yin
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hao Xu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenxiao Shi
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhe Li
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jie Zheng
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yulin Gan
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunzhong Chen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Baogen Shen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Ningbo Institute of Materials Technology & Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China
| | - Yuansha Chen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qinghua Zhang
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fengxia Hu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Ji-Rong Sun
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- School of Materials Science & Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, China
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Jilili J, Tolbatov I, Cossu F, Rahaman A, Fiser B, Kahaly MU. Atomic scale interfacial magnetism and origin of metal-insulator transition in (LaNiO[Formula: see text])[Formula: see text]/(CaMnO[Formula: see text])[Formula: see text] superlattices: a first principles study. Sci Rep 2023; 13:5056. [PMID: 36977694 PMCID: PMC10050077 DOI: 10.1038/s41598-023-30686-w] [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: 02/02/2022] [Accepted: 02/28/2023] [Indexed: 03/30/2023] Open
Abstract
Interfacial magnetism and metal-insulator transition at LaNiO[Formula: see text]-based oxide interfaces have triggered intense research efforts, because of the possible implications in future heterostructure device design and engineering. Experimental observation lack in some points a support from an atomistic view. In an effort to fill such gap, we hereby investigate the structural, electronic, and magnetic properties of (LaNiO[Formula: see text])[Formula: see text]/(CaMnO[Formula: see text])[Formula: see text] superlattices with varying LaNiO[Formula: see text] thickness (n) using density functional theory including a Hubbard-type effective on-site Coulomb term. We successfully capture and explain the metal-insulator transition and interfacial magnetic properties, such as magnetic alignments and induced Ni magnetic moments which were recently observed experimentally in nickelate-based heterostructures. In the superlattices modeled in our study, an insulating state is found for n=1 and a metallic character for n=2, 4, with major contribution from Ni and Mn 3d states. The insulating character originates from the disorder effect induced by sudden environment change for the octahedra at the interface, and associated to localized electronic states; on the other hand, for larger n, less localized interfacial states and increased polarity of the LaNiO[Formula: see text] layers contribute to metallicity. We discuss how the interplay between double and super-exchange interaction via complex structural and charge redistributions results in interfacial magnetism. While (LaNiO[Formula: see text])[Formula: see text]/(CaMnO[Formula: see text])[Formula: see text] superlattices are chosen as prototype and for their experimental feasibility, our approach is generally applicable to understand the intricate roles of interfacial states and exchange mechanism between magnetic ions towards the overall response of a magnetic interface or superlattice.
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Affiliation(s)
- J. Jilili
- ELI ALPS, ELI-HU Non-Profit Ltd., Wolfgang Sandner utca 3., Szeged, H-6728 Hungary
| | - I. Tolbatov
- Department of Pharmacy, University of Chieti-Pescara “G. d’Annunzio”, Chieti, Italy
- Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Paisos Catalans 16, 43007 Tarragona, Spain
| | - F. Cossu
- Asia Pacific Center for Theoretical Physics, Pohang, 37673 Korea
- Department of Physics and Institute of Quantum Convergence, Kangwon National University, 24341 Chuncheon, Korea
| | - A. Rahaman
- School of Mechanical Engineering, Vellore Institute of Technology, Vellore, 632014 India
| | - B. Fiser
- Higher Education and Industrial Cooperation Centre, University of Miskolc, Miskolc, 3515 Hungary
- Department of Physical Chemistry, University of Lodz, 90-236 Lodz, Poland
- Ferenc Rakoczi II Transcarpathian Hungarian College of Higher Education, 90200 Beregszász, Ukraine
| | - M. Upadhyay. Kahaly
- ELI ALPS, ELI-HU Non-Profit Ltd., Wolfgang Sandner utca 3., Szeged, H-6728 Hungary
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4
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Soltan S, Macke S, Ilse SE, Pennycook T, Zhang ZL, Christiani G, Benckiser E, Schütz G, Goering E. Ferromagnetic order controlled by the magnetic interface of LaNiO 3/La 2/3Ca 1/3MnO 3 superlattices. Sci Rep 2023; 13:3847. [PMID: 36890187 PMCID: PMC9995495 DOI: 10.1038/s41598-023-30814-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Accepted: 03/01/2023] [Indexed: 03/10/2023] Open
Abstract
Interface engineering in complex oxide superlattices is a growing field, enabling manipulation of the exceptional properties of these materials, and also providing access to new phases and emergent physical phenomena. Here we demonstrate how interfacial interactions can induce a complex charge and spin structure in a bulk paramagnetic material. We investigate a superlattice (SLs) consisting of paramagnetic LaNiO3 (LNO) and highly spin-polarized ferromagnetic La2/3Ca1/3MnO3 (LCMO), grown on SrTiO3 (001) substrate. We observed emerging magnetism in LNO through an exchange bias mechanism at the interfaces in X-ray resonant magnetic reflectivity. We find non-symmetric interface induced magnetization profiles in LNO and LCMO which we relate to a periodic complex charge and spin superstructure. High resolution scanning transmission electron microscopy images reveal that the upper and lower interfaces exhibit no significant structural variations. The different long range magnetic order emerging in LNO layers demonstrates the enormous potential of interfacial reconstruction as a tool for tailored electronic properties.
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Affiliation(s)
- S Soltan
- Physics Department, Faculty of Science, Helwan University, Helwan, Cairo, 11798, Egypt. .,Max Planck Institute for Intelligent Systems, Heisenbergstr. 3, 70569, Stuttgart, Germany. .,Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569, Stuttgart, Germany.
| | - S Macke
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569, Stuttgart, Germany
| | - S E Ilse
- Max Planck Institute for Intelligent Systems, Heisenbergstr. 3, 70569, Stuttgart, Germany
| | - T Pennycook
- EMAT, University of Antwerp Campus Groenenborger, 2020, Antwerp, Belgium.,Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090, Vienna, Austria
| | - Z L Zhang
- Erich-Schmid-Institute of Materials Science, Austrian Academy of Sciences, Jahnstraße 12, 8700, Leoben, Austria
| | - G Christiani
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569, Stuttgart, Germany
| | - E Benckiser
- Max Planck Institute for Solid State Research, Heisenbergstr. 1, 70569, Stuttgart, Germany
| | - G Schütz
- Max Planck Institute for Intelligent Systems, Heisenbergstr. 3, 70569, Stuttgart, Germany
| | - E Goering
- Max Planck Institute for Intelligent Systems, Heisenbergstr. 3, 70569, Stuttgart, Germany.
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5
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Control of Columnar Grain Microstructure in CSD LaNiO 3 Films. Molecules 2023; 28:molecules28041938. [PMID: 36838926 PMCID: PMC9959992 DOI: 10.3390/molecules28041938] [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: 01/19/2023] [Revised: 02/12/2023] [Accepted: 02/15/2023] [Indexed: 02/22/2023] Open
Abstract
Conductive LaNiO3 (LNO) films with an ABO3 perovskite structure deposited on silicon wafers are a promising material for various electronics applications. The creation of a well-defined columnar grain structure in CSD (Chemical Solution Deposition) LNO films is challenging to achieve on an amorphous substrate. Here, we report the formation of columnar grain structure in LNO films deposited on the Si-SiO2 substrate via layer-by-layer deposition with the control of soft-baking temperature and high temperature annealing time of each deposited layer. The columnar structure is controlled not by typical heterogeneous nucleation on the film/substrate interface, but by the crystallites' coalescence during the successive layers' deposition and annealing. The columnar structure of LNO film provides the low resistivity value ρ~700 µOhm·cm and is well suited to lead zirconate-titanate (PZT) film growth with perfect crystalline structure and ferroelectric performance. These results extend the understanding of columnar grain growth via CSD techniques and may enable the development of new materials and devices for distinct applications.
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6
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Zhou G, Li Z, Dou J, Ji H, Kang P, Shen Y, Wang S, Xu X. The polar and nonpolar interfaces influenced of magnetism in LaMnO 3-based superlattices. RSC Adv 2023; 13:10254-10260. [PMID: 37006349 PMCID: PMC10065140 DOI: 10.1039/d3ra00229b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 03/28/2023] [Indexed: 04/03/2023] Open
Abstract
The interface of perovskite heterostructures has been shown to exhibit various electronic and magnetic phases such as two-dimensional electron gas, magnetism, superconductivity, and electronic phase separation. These rich phases are expected due to the strong interplay between spin, charge, and orbital degree of freedom at the interface. In this work, the polar and nonpolar interfaces are designed in LaMnO3-based (LMO) superlattices to investigate the difference in magnetic and transport properties. For the polar interface in a LMO/SrMnO3 superlattice, a novel robust ferromagnetism, exchange bias effect, vertical magnetization shift, and metallic behaviors coexist due to the polar catastrophe, which results in a double exchange coupling effect in the interface. For the nonpolar interface in a LMO/LaNiO3 superlattice, only the ferromagnetism and exchange bias effect characteristics exist due to the polar continuous interface. This is attributed to the charge transfer between Mn3+ and Ni3+ ions at the interface. Therefore, transition metal oxides exhibit various novel physical properties due to the strong correlation of d electrons and the polar and nonpolar interfaces. Our observations may provide an approach to further tune the properties using the selected polar and nonpolar oxide interfaces. The interface of perovskite heterostructures has been shown to exhibit various electronic and magnetic phases such as two-dimensional electron gas, magnetism, superconductivity, and electronic phase separation![]()
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Affiliation(s)
- Guowei Zhou
- School of Chemistry and Materials Science of Shanxi Normal University, Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of EducationTaiyuan 030006China
- Research Institute of Materials Science of Shanxi Normal University, Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and TechonologyTaiyuan 030006China
| | - Zhilan Li
- School of Chemistry and Materials Science of Shanxi Normal University, Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of EducationTaiyuan 030006China
| | - Jiarui Dou
- School of Chemistry and Materials Science of Shanxi Normal University, Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of EducationTaiyuan 030006China
| | - Huihui Ji
- School of Chemistry and Materials Science of Shanxi Normal University, Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of EducationTaiyuan 030006China
- Research Institute of Materials Science of Shanxi Normal University, Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and TechonologyTaiyuan 030006China
| | - Penghua Kang
- School of Chemistry and Materials Science of Shanxi Normal University, Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of EducationTaiyuan 030006China
| | - Yufan Shen
- School of Chemistry and Materials Science of Shanxi Normal University, Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of EducationTaiyuan 030006China
| | - Siqi Wang
- School of Chemistry and Materials Science of Shanxi Normal University, Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of EducationTaiyuan 030006China
| | - Xiaohong Xu
- School of Chemistry and Materials Science of Shanxi Normal University, Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of EducationTaiyuan 030006China
- Research Institute of Materials Science of Shanxi Normal University, Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and TechonologyTaiyuan 030006China
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7
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Guasco L, Khaydukov Y, Kim G, Keller T, Vorobiev A, Devishvili A, Wochner P, Christiani G, Logvenov G, Keimer B. Emergent Magnetic Fan Structures in Manganite Homojunction Arrays. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2202971. [PMID: 35817958 DOI: 10.1002/adma.202202971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 06/27/2022] [Indexed: 06/15/2023]
Abstract
Devices with tunable magnetic noncollinearity are important components of superconducting electronics and spintronics, but they typically require epitaxial integration of several complex materials. The spin-polarized neutron reflectometry measurements on La1-x Srx MnO3 homojunction arrays with modulated Sr concentration reported herein have led to the discovery of magnetic fan structures with highly noncollinear alignment of Mn spins and an emergent periodicity twice as large as the array's unit cell. The neutron data show that these magnetic superstructures can be fully long-range ordered, despite the gradual modulation of the doping level created by charge transfer and chemical intermixing. The degree of noncollinearity can be effectively adjusted by low magnetic fields. Notwithstanding their chemical and structural simplicity, oxide homojunctions thus show considerable promise as a platform for tunable complex magnetism and as a powerful design element of spintronic devices.
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Affiliation(s)
- Laura Guasco
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
- Max Planck Society Outstation at the Heinz Maier-Leibnitz Zentrum (MLZ), D-85748, Garching, Germany
| | - Yury Khaydukov
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
- Max Planck Society Outstation at the Heinz Maier-Leibnitz Zentrum (MLZ), D-85748, Garching, Germany
| | - Gideok Kim
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
| | - Thomas Keller
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
- Max Planck Society Outstation at the Heinz Maier-Leibnitz Zentrum (MLZ), D-85748, Garching, Germany
| | - Alexei Vorobiev
- Institut Laue-Langevin, 71 avenue des Martyrs, CS 20156, Grenoble Cedex 9, F-38042, France
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala, 751 20, Sweden
| | - Anton Devishvili
- Institut Laue-Langevin, 71 avenue des Martyrs, CS 20156, Grenoble Cedex 9, F-38042, France
- Department of Physics and Astronomy, Uppsala University, Box 516, Uppsala, 751 20, Sweden
| | - Peter Wochner
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
| | - Georg Christiani
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
| | - Gennady Logvenov
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
| | - Bernhard Keimer
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, D-70569, Stuttgart, Germany
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8
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Resonant Soft X-ray Reflectivity in the Study of Magnetic Properties of Low-Dimensional Systems. MAGNETOCHEMISTRY 2021. [DOI: 10.3390/magnetochemistry7100136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this review, the technique of resonant soft X-ray reflectivity in the study of magnetic low-dimensional systems is discussed. This technique is particularly appealing in the study of magnetization at buried interfaces and to discriminate single elemental contributions to magnetism, even when this is ascribed to few atoms. The major fields of application are described, including magnetic proximity effects, thin films of transition metals and related oxides, and exchange-bias systems. The fundamental theoretical background leading to dichroism effects in reflectivity is also briefly outlined.
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9
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Caputo M, Ristic Z, Dhaka RS, Das T, Wang Z, Matt CE, Plumb NC, Guedes EB, Jandke J, Naamneh M, Zakharova A, Medarde M, Shi M, Patthey L, Mesot J, Piamonteze C, Radović M. Proximity-Induced Novel Ferromagnetism Accompanied with Resolute Metallicity in NdNiO 3 Heterostructure. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2021; 8:e2101516. [PMID: 34382373 PMCID: PMC8498901 DOI: 10.1002/advs.202101516] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/25/2021] [Indexed: 06/13/2023]
Abstract
Employing X-ray magnetic circular dichroism (XMCD), angle-resolved photoemission spectroscopy (ARPES), and momentum-resolved density fluctuation (MRDF) theory, the magnetic and electronic properties of ultrathin NdNiO3 (NNO) film in proximity to ferromagnetic (FM) La0.67 Sr0.33 MnO3 (LSMO) layer are investigated. The experimental data shows the direct magnetic coupling between the nickelate film and the manganite layer which causes an unusual ferromagnetic (FM) phase in NNO. Moreover, it is shown the metal-insulator transition in the NNO layer, identified by an abrupt suppression of ARPES spectral weight near the Fermi level (EF ), is absent. This observation suggests that the insulating AFM ground state is quenched in proximity to the FM layer. Combining the experimental data (XMCD and AREPS) with the momentum-resolved density fluctuation calculation (MRDF) reveals a direct link between the MIT and the magnetic orders in NNO systems. This work demonstrates that the proximity layer order can be broadly used to modify physical properties and enrich the phase diagram of RENiO3 (RE = rare-earth element).
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Affiliation(s)
- Marco Caputo
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
| | - Zoran Ristic
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
- Institute of Condensed Matter PhysicsEcole Polytechnique Fédérale de Lausanne (EPFL)LausanneCH‐1015Switzerland
- Vinca Institute of Nuclear SciencesUniversity of BelgradeP.O.Box 522Belgrade11000Serbia
| | - Rajendra S. Dhaka
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
- Institute of Condensed Matter PhysicsEcole Polytechnique Fédérale de Lausanne (EPFL)LausanneCH‐1015Switzerland
- Department of PhysicsIndian Institute of Technology Delhi, Hauz KhasNew Delhi110016India
| | - Tanmoy Das
- Department of PhysicsIndian Institute of ScienceBangalore560012India
| | - Zhiming Wang
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
- CAS Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingboZhejiang315201China
| | - Christan E. Matt
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
| | - Nicholas C. Plumb
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
| | - Eduardo B. Guedes
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
| | - Jasmin Jandke
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
| | - Muntaser Naamneh
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
| | - Anna Zakharova
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
| | - Marisa Medarde
- Laboratory for Multiscale Materials ExperimentsPaul Scherrer InstitutVilligenCH‐5232Switzerland
| | - Ming Shi
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
| | - Luc Patthey
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
| | - Joël Mesot
- Paul Scherrer InstituteVilligenCH‐5232Switzerland
| | - Cinthia Piamonteze
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
| | - Milan Radović
- Photon Science DivisionPaul Scherrer InstituteVilligenCH‐5232Switzerland
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10
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Andreeva M, Smekhova A, Baulin R, Repchenko Y, Bali R, Schmitz-Antoniak C, Wende H, Sergueev I, Schlage K, Wille HC. Evolution of the magnetic hyperfine field profiles in an ion-irradiated Fe 60Al 40 film measured by nuclear resonant reflectivity. JOURNAL OF SYNCHROTRON RADIATION 2021; 28:1535-1543. [PMID: 34475301 DOI: 10.1107/s1600577521007694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 07/27/2021] [Indexed: 06/13/2023]
Abstract
Nuclear resonant reflectivity (NRR) from an Fe60Al40 film was measured using synchrotron radiation at several grazing angles near the critical angle of total external reflection. Using laterally resolved measurements after irradiation with 20 keV Ne+ ions of gradually varying fluence of 0-3.0 × 1014 ions cm-2, the progressive creation of the ferromagnetic A2 phase with increasing ion fluence was confirmed. The observed depth selectivity of the method has been explained by application of the standing wave approach. From the time spectra of the nuclear resonant scattering in several reflection directions the depth profiles for different hyperfine fields were extracted. The results show that the highest magnetic hyperfine fields (∼18-23 T) are initially created in the central part of the film and partially at the bottom interface with the SiO2 substrate. The evolution of the ferromagnetic onset, commencing at a fixed depth within the film and propagating towards the interfaces, has been directly observed. At higher fluence (3.0 × 1014 ions cm-2) the depth distribution of the ferromagnetic fractions became more homogeneous across the film depth, in accordance with previous results.
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Affiliation(s)
- Marina Andreeva
- Faculty of Physics, M. V. Lomonosov Moscow State University, Moscow 119991, Russian Federation
| | - Alevtina Smekhova
- Peter Grünberg Institute (PGI-6), Jülich Research Center, 52425 Jülich, Germany
| | - Roman Baulin
- Faculty of Physics, M. V. Lomonosov Moscow State University, Moscow 119991, Russian Federation
| | - Yurii Repchenko
- National Research Centre `Kurchatov Institute', Pl. Kurchatova 1, Moscow 123182, Russian Federation
| | - Rantej Bali
- Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, 01328 Dresden, Germany
| | | | - Heiko Wende
- Faculty of Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University of Duisburg-Essen, 47048 Duisburg, Germany
| | - Ilya Sergueev
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - Kai Schlage
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
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11
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Mundet B, Domínguez C, Fowlie J, Gibert M, Triscone JM, Alexander DTL. Near-Atomic-Scale Mapping of Electronic Phases in Rare Earth Nickelate Superlattices. NANO LETTERS 2021; 21:2436-2443. [PMID: 33685129 PMCID: PMC7995248 DOI: 10.1021/acs.nanolett.0c04538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 01/29/2021] [Indexed: 06/12/2023]
Abstract
Nanoscale mapping of the distinct electronic phases characterizing the metal-insulator transition displayed by most of the rare-earth nickelate compounds is fundamental for discovering the true nature of this transition and the possible couplings that are established at the interfaces of nickelate-based heterostructures. Here, we demonstrate that this can be accomplished by using scanning transmission electron microscopy in combination with electron energy-loss spectroscopy. By tracking how the O K and Ni L edge fine structures evolve across two different NdNiO3/SmNiO3 superlattices, displaying either one or two metal-insulator transitions depending on the individual layer thickness, we are able to determine the electronic state of each of the individual constituent materials. We further map the spatial configuration associated with their metallic/insulating regions, reaching unit cell spatial resolution. With this, we estimate the width of the metallic/insulating boundaries at the NdNiO3/SmNiO3 interfaces, which is measured to be on the order of four unit cells.
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Affiliation(s)
- Bernat Mundet
- Department
of Quantum Matter Physics, University of
Geneva, 1211 Geneva, Switzerland
- Electron
Spectrometry and Microscopy Laboratory (LSME), Institute of Physics
(IPHYS), École Polytechnique Fédérale
de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Claribel Domínguez
- Department
of Quantum Matter Physics, University of
Geneva, 1211 Geneva, Switzerland
| | - Jennifer Fowlie
- Department
of Quantum Matter Physics, University of
Geneva, 1211 Geneva, Switzerland
| | - Marta Gibert
- Physik-Institut, University of Zurich, 8057 Zurich, Switzerland
| | - Jean-Marc Triscone
- Department
of Quantum Matter Physics, University of
Geneva, 1211 Geneva, Switzerland
| | - Duncan T. L. Alexander
- Electron
Spectrometry and Microscopy Laboratory (LSME), Institute of Physics
(IPHYS), École Polytechnique Fédérale
de Lausanne (EPFL), 1015 Lausanne, Switzerland
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12
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Atomic-scale determination of spontaneous magnetic reversal in oxide heterostructures. Proc Natl Acad Sci U S A 2019; 116:10309-10316. [PMID: 31068468 DOI: 10.1073/pnas.1819570116] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Interfaces between transition metal oxides are known to exhibit emerging electronic and magnetic properties. Here we report intriguing magnetic phenomena for La2/3Sr1/3MnO3 films on an SrTiO3 (001) substrate (LSMO/STO), where the interface governs the macroscopic properties of the entire monolithic thin film. The interface is characterized on the atomic level utilizing scanning transmission electron microscopy and electron energy loss spectroscopy (STEM-EELS), and density functional theory (DFT) is employed to elucidate the physics. STEM-EELS reveals mixed interfacial stoichiometry, subtle lattice distortions, and oxidation-state changes. Magnetic measurements combined with DFT calculations demonstrate that a unique form of antiferromagnetic exchange coupling appears at the interface, generating a novel exchange spring-type interaction that results in a remarkable spontaneous magnetic reversal of the entire ferromagnetic film, and an inverted magnetic hysteresis, persisting above room temperature. Formal oxidation states derived from electron spectroscopy data expose the fact that interfacial oxidation states are not consistent with nominal charge counting. The present work demonstrates the necessity of atomically resolved electron microscopy and spectroscopy for interface studies. Theory demonstrates that interfacial nonstoichiometry is an essential ingredient, responsible for the observed physical properties. The DFT-calculated electrostatic potential is flat in both the LSMO and STO sides (no internal electric field) for both Sr-rich and stoichiometric interfaces, while the DFT-calculated charge density reveals no charge transfer/accumulation at the interface, indicating that oxidation-state changes do not necessarily reflect charge transfer and that the concept of polar mismatch is not applicable in metal-insulator polar-nonpolar interfaces.
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13
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Andreeva MA, Baulin RA, Repchenko YL. Standing wave approach in the theory of X-ray magnetic reflectivity. JOURNAL OF SYNCHROTRON RADIATION 2019; 26:483-496. [PMID: 30855259 DOI: 10.1107/s1600577518018398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 12/28/2018] [Indexed: 06/09/2023]
Abstract
An extension of the exact X-ray resonant magnetic reflectivity theory has been developed, taking into account the small value of the magnetic terms in the X-ray susceptibility tensor. It is shown that squared standing waves (fourth power of the total electric field) determine the output of the magnetic addition to the total reflectivity from a magnetic multilayer. The obtained generalized kinematical approach essentially speeds up the calculation of the asymmetry ratio in the magnetic reflectivity. The developed approach easily explains the peculiarities of the angular dependence of the reflectivity with the rotated polarization (such as the peak at the critical angle of the total external reflection). The revealed dependence of the magnetic part of the total reflectivity on the squared standing waves means that the selection of the reflectivity with the rotated polarization ensures higher sensitivity to the depth profiles of magnetization than the secondary radiation at the specular reflection condition.
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Affiliation(s)
- M A Andreeva
- Faculty of Physics, M. V. Lomonosov Moscow State University, Moscow 119991, Russian Federation
| | - R A Baulin
- Faculty of Physics, M. V. Lomonosov Moscow State University, Moscow 119991, Russian Federation
| | - Yu L Repchenko
- National Research Centre `Kurchatov Institute', Pl. Kurchatova 1, Moscow 123182, Russian Federation
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14
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Symmetry mismatch-driven perpendicular magnetic anisotropy for perovskite/brownmillerite heterostructures. Nat Commun 2018; 9:1923. [PMID: 29765023 PMCID: PMC5953968 DOI: 10.1038/s41467-018-04304-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 04/18/2018] [Indexed: 12/22/2022] Open
Abstract
Grouping different transition metal oxides together by interface engineering is an important route toward emergent phenomenon. While most of the previous works focused on the interface effects in perovskite/perovskite heterostructures, here we reported on a symmetry mismatch-driven spin reorientation toward perpendicular magnetic anisotropy in perovskite/brownmillerite heterostructures, which is scarcely seen in tensile perovskite/perovskite heterostructures. We show that alternately stacking perovskite La2/3Sr1/3MnO3 and brownmillerite LaCoO2.5 causes a strong interface reconstruction due to symmetry discontinuity at interface: neighboring MnO6 octahedra and CoO4 tetrahedra at the perovskite/brownmillerite interface cooperatively relax in a manner that is unavailable for perovskite/perovskite interface, leading to distinct orbital reconstructions and thus the perpendicular magnetic anisotropy. Moreover, the perpendicular magnetic anisotropy is robust, with an anisotropy constant two orders of magnitude greater than the in-plane anisotropy of the perovskite/perovskite interface. The present work demonstrates the great potential of symmetry engineering in designing artificial materials on demand. Complex oxide heterostructures exhibit multifunctional behaviour that could be used in a range of device applications. Here, the authors observe that reconstruction at oxide perovskite/brownmillerite interfaces leads to perpendicular magnetic spin orientation, with potential use in spintronic devices.
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15
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Catalano S, Gibert M, Fowlie J, Íñiguez J, Triscone JM, Kreisel J. Rare-earth nickelates RNiO 3: thin films and heterostructures. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:046501. [PMID: 29266004 DOI: 10.1088/1361-6633/aaa37a] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
This review stands in the larger framework of functional materials by focussing on heterostructures of rare-earth nickelates, described by the chemical formula RNiO3 where R is a trivalent rare-earth R = La, Pr, Nd, Sm, …, Lu. Nickelates are characterized by a rich phase diagram of structural and physical properties and serve as a benchmark for the physics of phase transitions in correlated oxides where electron-lattice coupling plays a key role. Much of the recent interest in nickelates concerns heterostructures, that is single layers of thin film, multilayers or superlattices, with the general objective of modulating their physical properties through strain control, confinement or interface effects. We will discuss the extensive studies on nickelate heterostructures as well as outline different approaches to tuning and controlling their physical properties and, finally, review application concepts for future devices.
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Affiliation(s)
- S Catalano
- DQMP, Université de Genève, 24 Quai Ernest-Ansermet, 1211 Geneva, Switzerland
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16
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Zhou G, Jiang F, Zang J, Quan Z, Xu X. Observation of Superconductivity in the LaNiO 3/La 0.7Sr 0.3MnO 3 Superlattice. ACS APPLIED MATERIALS & INTERFACES 2018; 10:1463-1467. [PMID: 29286234 DOI: 10.1021/acsami.7b17603] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In the pursuit of high-temperature superconductivity like that in cuprates, artificial heterostructures or interfaces have attracted tremendous interest. It has been a long-sought goal to find similar unconventional superconductivity in nickelates. However, as far as we know, this has not yet been experimentally realized. To approach this objective, we synthesized a prototypical superlattice that consists of ultrathin LaNiO3 and La0.7Sr0.3MnO3 layers. Both zero resistance and the Meissner effect are observed using resistive and magnetic measurements of the superlattice. These are experimental indicators for superconductivity in new superconductors. X-ray linear dichroism causes the NiO2 planes to develop electron-occupied x2-y2 orbital order similar to that of cuprate-based superconductors. Our findings demonstrate that artificial interface engineering is suitable for investigating novel physical phenomena, such as superconductivity.
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Affiliation(s)
- Guowei Zhou
- School of Chemistry and Materials Science, Key Laboratory of Magnetic Molecules and Magnetic Information Materials, Ministry of Education, Shanxi Normal University , Linfen 041004, China
- Research Institute of Materials Science of Shanxi Normal University & Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and Techonology , Linfen 041004, China
| | - Fengxian Jiang
- School of Chemistry and Materials Science, Key Laboratory of Magnetic Molecules and Magnetic Information Materials, Ministry of Education, Shanxi Normal University , Linfen 041004, China
- Research Institute of Materials Science of Shanxi Normal University & Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and Techonology , Linfen 041004, China
| | - Julu Zang
- School of Chemistry and Materials Science, Key Laboratory of Magnetic Molecules and Magnetic Information Materials, Ministry of Education, Shanxi Normal University , Linfen 041004, China
| | - Zhiyong Quan
- School of Chemistry and Materials Science, Key Laboratory of Magnetic Molecules and Magnetic Information Materials, Ministry of Education, Shanxi Normal University , Linfen 041004, China
- Research Institute of Materials Science of Shanxi Normal University & Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and Techonology , Linfen 041004, China
| | - Xiaohong Xu
- School of Chemistry and Materials Science, Key Laboratory of Magnetic Molecules and Magnetic Information Materials, Ministry of Education, Shanxi Normal University , Linfen 041004, China
- Research Institute of Materials Science of Shanxi Normal University & Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and Techonology , Linfen 041004, China
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17
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Perret E, Sen K, Khmaladze J, Mallett BPP, Yazdi-Rizi M, Marsik P, Das S, Marozau I, Uribe-Laverde MA, de Andrés Prada R, Strempfer J, Döbeli M, Biškup N, Varela M, Mathis YL, Bernhard C. Structural, magnetic and electronic properties of pulsed-laser-deposition grown SrFeO 3-δ thin films and SrFeO 3-δ /La 2/3Ca 1/3MnO 3 multilayers. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:495601. [PMID: 29134950 DOI: 10.1088/1361-648x/aa93a6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We studied the structural, magnetic and electronic properties of [Formula: see text] (SFO) thin films and [Formula: see text]/[Formula: see text] [Formula: see text]MnO3 (LCMO) superlattices that have been grown with pulsed laser deposition (PLD) on [Formula: see text] [Formula: see text] [Formula: see text] [Formula: see text] [Formula: see text] (LSAT) substrates. X-ray reflectometry and scanning transmission electron microscopy (STEM) confirm the high structural quality of the films and flat and atomically sharp interfaces of the superlattices. The STEM data also reveal a difference in the interfacial layer stacking with a SrO layer at the LCMO/SFO and a LaO layer at the SFO/LCMO interfaces along the PLD growth direction. The x-ray diffraction (XRD) data suggest that the as grown SFO films and SFO/LCMO superlattices have an oxygen-deficient [Formula: see text] structure with I4/ mmm space group symmetry ([Formula: see text]). Subsequent ozone annealed SFO films are consistent with an almost oxygen stoichiometric structure ([Formula: see text]). The electronic and magnetic properties of these SFO films are similar to the ones of corresponding single crystals. In particular, the as grown [Formula: see text] films are insulating whereas the ozone annealed films are metallic. The magneto-resistance effects of the as grown SFO films have a similar magnitude as in the single crystals, but extend over a much wider temperature range. Last but not least, for the SFO/LCMO superlattices we observe a rather large exchange bias effect that varies as a function of the cooling field.
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Affiliation(s)
- E Perret
- University of Fribourg, Department of Physics and Fribourg Center for Nanomaterials, Chemin du Musée 3, CH-1700 Fribourg, Switzerland
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18
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Zhou G, Yan Z, Bai Y, Zang J, Quan Z, Qi S, Xu X. Exchange Bias Effect and Orbital Reconstruction in (001)-Oriented LaMnO 3/LaNiO 3 Superlattices. ACS APPLIED MATERIALS & INTERFACES 2017; 9:39855-39862. [PMID: 29057645 DOI: 10.1021/acsami.7b14503] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Paramagnetic LaNiO3 (LNO)-based heterostructures have been attracting the attention of researches, especially since the interesting exchange bias (EB) effect has been observed in (111)-oriented LaMnO3 (LMO)/LNO superlattices (SLs). However, this effect is not expected to occur in the (001) direction SLs. In this paper, we report the observation of an unexpected EB effect in (001)-oriented (LMO)3/(LNO)t SLs. The orbits of interfacial Mn/Ni ions preferentially occupy the strain-stabilized x2 - y2 in ultrathin LNO layers [t ≤ 4 unit cells (u.c.)]. Conversely, as the LNO layer becomes thicker (t ≥ 6 u.c.), the EB effect is absent, and the orbits are reconstructed to form the 3z2 - r2 preferential occupancy. The absence of the EB in thicker LNO-based SLs is attributed to the interfacial charge transfer suppressed by orbital reconstruction as a consequence of the increasing LNO thickness. In the thinner LNO-based SLs, the larger charge transfer results in stronger localized magnetic moments for the cause of the EB effect. These results provide a useful interpretation of the relationship between macroscopic magnetic properties and the microscopic electronic structure in oxide-based heterostructures.
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Affiliation(s)
- Guowei Zhou
- School of Chemistry and Materials Science of Shanxi Normal University & Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education , Linfen 041004, China
- Research Institute of Materials Science of Shanxi Normal University & Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and Techonology , Linfen 041004, China
| | - Zhi Yan
- School of Chemistry and Materials Science of Shanxi Normal University & Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education , Linfen 041004, China
| | - Yuhao Bai
- Research Institute of Materials Science of Shanxi Normal University & Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and Techonology , Linfen 041004, China
| | - Julu Zang
- School of Chemistry and Materials Science of Shanxi Normal University & Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education , Linfen 041004, China
| | - Zhiyong Quan
- School of Chemistry and Materials Science of Shanxi Normal University & Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education , Linfen 041004, China
- Research Institute of Materials Science of Shanxi Normal University & Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and Techonology , Linfen 041004, China
| | - Shifei Qi
- School of Chemistry and Materials Science of Shanxi Normal University & Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education , Linfen 041004, China
- Research Institute of Materials Science of Shanxi Normal University & Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and Techonology , Linfen 041004, China
| | - Xiaohong Xu
- School of Chemistry and Materials Science of Shanxi Normal University & Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education , Linfen 041004, China
- Research Institute of Materials Science of Shanxi Normal University & Collaborative Innovation Center for Shanxi Advanced Permanent Magnetic Materials and Techonology , Linfen 041004, China
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19
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Chen B, Xu H, Ma C, Mattauch S, Lan D, Jin F, Guo Z, Wan S, Chen P, Gao G, Chen F, Su Y, Wu W. All-oxide–based synthetic antiferromagnets exhibiting layer-resolved magnetization reversal. Science 2017; 357:191-194. [DOI: 10.1126/science.aak9717] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 06/07/2017] [Indexed: 11/02/2022]
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20
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Chen H, Millis A. Charge transfer driven emergent phenomena in oxide heterostructures. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:243001. [PMID: 28437253 DOI: 10.1088/1361-648x/aa6efe] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Complex oxides exhibit many intriguing phenomena, including metal-insulator transition, ferroelectricity/multiferroicity, colossal magnetoresistance and high transition temperature superconductivity. Advances in epitaxial thin film growth techniques enable us to combine different complex oxides with atomic precision and form an oxide heterostructure. Recent theoretical and experimental work has shown that charge transfer across oxide interfaces generally occurs and leads to a great diversity of emergent interfacial properties which are not exhibited by bulk constituents. In this report, we review mechanisms and physical consequence of charge transfer across interfaces in oxide heterostructures. Both theoretical proposals and experimental measurements of various oxide heterostructures are discussed and compared. We also review the theoretical methods that are used to calculate charge transfer across oxide interfaces and discuss the success and challenges in theory. Finally, we present a summary and perspectives for future research.
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Affiliation(s)
- Hanghui Chen
- NYU-ECNU Institute of Physics, New York University Shanghai, 200062, People's Republic of China. Department of Physics, New York University, New York, NY 10002, United States of America
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21
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Zhou G, Song C, Bai Y, Quan Z, Jiang F, Liu W, Xu Y, Dhesi SS, Xu X. Robust Interfacial Exchange Bias and Metal-Insulator Transition Influenced by the LaNiO 3 Layer Thickness in La 0.7Sr 0.3MnO 3/LaNiO 3 Superlattices. ACS APPLIED MATERIALS & INTERFACES 2017; 9:3156-3160. [PMID: 28067035 DOI: 10.1021/acsami.6b14372] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Artificial heterostructures based on LaNiO3 (LNO) have been widely investigated with the aim to realize the insulating antiferromagnetic state of LNO. In this work, we grew [(La0.7Sr0.3MnO3)5-(LaNiO3)n]12 superlattices on (001)-oriented SrTiO3 substrates by pulsed laser deposition and observed an unexpected exchange bias effect in field-cooled hysteresis loops. Through X-ray absorption spectroscopy and magnetic circular dichroism experiments, we found that the charge transfer at the interfacial Mn and Ni ions can induce a localized magnetic moment. A remarkable increase of exchange bias field and a transition from metal to insulator were simultaneously observed upon decreasing the thickness of the LNO layer, indicating the antiferromagnetic insulator state in 2 unit cells LNO ultrathin layers. The robust exchange bias of 745 Oe in the superlattice is caused by an interfacial localized magnetic moment and an antiferromagnetic state in the ultrathin LNO layer, pinning the ferromagnetic La0.7Sr0.3MnO3 layers together. Our results demonstrate that artificial interface engineering is a useful method to realize novel magnetic and transport properties.
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Affiliation(s)
- Guowei Zhou
- School of Chemistry and Materials Science, Key Laboratory of Magnetic Molecules and Magnetic Information Materials, Ministry of Education, Shanxi Normal University , Linfen 041004, China
- Research Institute of Materials Science, Shanxi Normal University , Linfen 041004, China
| | - Cheng Song
- Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University , Beijing 100084, China
| | - Yuhao Bai
- School of Chemistry and Materials Science, Key Laboratory of Magnetic Molecules and Magnetic Information Materials, Ministry of Education, Shanxi Normal University , Linfen 041004, China
- Research Institute of Materials Science, Shanxi Normal University , Linfen 041004, China
| | - Zhiyong Quan
- School of Chemistry and Materials Science, Key Laboratory of Magnetic Molecules and Magnetic Information Materials, Ministry of Education, Shanxi Normal University , Linfen 041004, China
- Research Institute of Materials Science, Shanxi Normal University , Linfen 041004, China
| | - Fengxian Jiang
- School of Chemistry and Materials Science, Key Laboratory of Magnetic Molecules and Magnetic Information Materials, Ministry of Education, Shanxi Normal University , Linfen 041004, China
- Research Institute of Materials Science, Shanxi Normal University , Linfen 041004, China
| | - Wenqing Liu
- Spintronics and Nanodevice Laboratory, Department of Electronics, University of York , York YO10 5DD, U.K
- Department of Electronic Engineering, Royal Holloway, University of London , Egham, Surrey TW20 0EX, U.K
| | - Yongbing Xu
- Spintronics and Nanodevice Laboratory, Department of Electronics, University of York , York YO10 5DD, U.K
| | - Sarnjeet S Dhesi
- Harwell Science and Innovation Campus, Diamond Light Source , Didcot, Oxfordshire OX11 0DE, U.K
| | - Xiaohong Xu
- School of Chemistry and Materials Science, Key Laboratory of Magnetic Molecules and Magnetic Information Materials, Ministry of Education, Shanxi Normal University , Linfen 041004, China
- Research Institute of Materials Science, Shanxi Normal University , Linfen 041004, China
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