|
1
|
Kelley KP, Sharma V, Zhang W, Baddorf AP, Nascimento VB, Vasudevan RK. Exotic Long-Range Surface Reconstruction on La 0.7Sr 0.3MnO 3 Thin Films. ACS APPLIED MATERIALS & INTERFACES 2021; 13:9166-9173. [PMID: 33566561 DOI: 10.1021/acsami.0c20166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Due to an extremely diverse phase space, La1-xSrxMnO3, as with other manganites, offers a wide range of tunability and applications including colossal magnetoresistance and use as spin-polarized electrodes. Here, we study an unprecedented, exotic surface reconstruction (6 × 6) in La1-xSrxMnO3 (x = 0.3) observed via low-energy electron diffraction (LEED). Scanning tunneling microscopy (STM) shows the surface is relatively flat, with unit-cell step heights, and X-ray photoelectron spectroscopy (XPS) reveals a strong degree of Sr segregation at the surface. By combining electron diffraction and first-principles computations, we propose that the long-range surface reconstruction consists of a Sr-segregated surface with La (6 × 6) ordering. This study expands our understanding of manganite systems and underscores their ability to form interesting surface reconstructions, driven largely by cation segregation that can potentially be controlled for tuning surface ordering.
Collapse
Affiliation(s)
- Kyle P Kelley
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Vinit Sharma
- National Institute for Computational Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Joint Institute for Computational Sciences, University of Tennessee, Knoxville, Tennessee 37996, United States
| | - Wenrui Zhang
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Arthur P Baddorf
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Von B Nascimento
- Departamento de Física, Universidade Federal de Minas Gerais, Avenida Antônio Carlos, 6627, Belo Horizonte 31270-901, MG, Brazil
| | - Rama K Vasudevan
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| |
Collapse
|
|
2
|
Chen A, Wang Q, Fitzsimmons MR, Enriquez E, Weigand M, Harrell Z, McFarland B, Lü X, Dowden P, MacManus-Driscoll JL, Yarotski D, Jia Q. Hidden Interface Driven Exchange Coupling in Oxide Heterostructures. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2017; 29:1700672. [PMID: 28464394 DOI: 10.1002/adma.201700672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 03/15/2017] [Indexed: 06/07/2023]
Abstract
A variety of emergent phenomena have been enabled by interface engineering in complex oxides. The existence of an intrinsic interfacial layer has often been found at oxide heterointerfaces. However, the role of such an interlayerin controlling functionalities is not fully explored. Here, we report the control of the exchange bias (EB) in single-phase manganite thin films with nominallyuniform chemical composition across the interfaces. The sign of EB depends on the magnitude of the cooling field. A pinned layer, confirmed by polarized neutron reflectometry, provides the source of unidirectional anisotropy. The origin of the exchange bias coupling is discussed in terms of magnetic interactions between the interfacial ferromagnetically reduced layer and the bulk ferromagnetic region. The sign of EB is related to the frustration of antiferromagnetic coupling between the ferromagnetic region and the pinned layer. Our results shed new light on using oxide interfaces to design functional spintronic devices.
Collapse
Affiliation(s)
- Aiping Chen
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Qiang Wang
- Materials Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
- Department of Physics and Astronomy, West Virginia University, Morgantown, WV, 26506, USA
| | - Michael R Fitzsimmons
- Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN, 37996, USA
| | - Erik Enriquez
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Marcus Weigand
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Zach Harrell
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Brian McFarland
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Xujie Lü
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Paul Dowden
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | | | - Dmitry Yarotski
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
| | - Quanxi Jia
- Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, NM, 87545, USA
- Department of Materials Design and Innovation, University at Buffalo - The State University of New York, Buffalo, NY, 14260, USA
| |
Collapse
|