Ferromagnetic-Antiferromagnetic Coupling by Distortion of Fe/Mn Oxygen Octahedrons in (BiFeO3 )m (La0.7 Sr0.3 MnO3 )n Superlattices

Jie Xiong; Tianyu Lei; Junwei Chu; Chao Yang; Jiake Wei; Mujin Zhuo; Eun-Mi Choi; Bowan Tao; Wanli Zhang; Yongqiang Wang; Yanrong Li

doi:10.1002/smll.201700107

Ferromagnetic-Antiferromagnetic Coupling by Distortion of Fe/Mn Oxygen Octahedrons in (BiFeO₃ )_m (La_0.7 Sr_0.3 MnO₃ )_n Superlattices

Small. 2017 May;13(18). doi: 10.1002/smll.201700107. Epub 2017 Mar 10.

Authors

Jie Xiong¹, Tianyu Lei¹, Junwei Chu¹, Chao Yang¹, Jiake Wei¹, Mujin Zhuo², Eun-Mi Choi³, Bowan Tao¹, Wanli Zhang¹, Yongqiang Wang², Yanrong Li¹

Affiliations

¹ State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu, 610054, China.
² Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, 87545, USA.
³ Department of Materials Science, University of Cambridge, 27 Charles Babbage Road, Cambridge, CB3 0FS, UK.

PMID: 28294569
DOI: 10.1002/smll.201700107

Abstract

Interface enhanced magnetism attracts much attention due to its potential use in exploring novel structure devices. Nevertheless, the magnetic behavior at interfaces has not been quantitatively determined. In this study, abnormal magnetic moment reduction is observed in La_0.7 Sr_0.3 MnO₃ (LSMO)/BiFeO₃ (BFO) superlattices, which is induced by ferromagnetic (FM)/antiferromagnetic (AFM) coupling in the interface. With reduced repetition of the superlattice's unit cell [(LSMO)_n /(BFO)_n ]_60/_n (n = 1, 2, 5, 10) on a SrTiO₃ substrate, magnetic moment reduction from 25.5 emu cc^-1 ([(LSMO)₁₀ /(BFO)₁₀ ]₆ ) to 1.5 emu cc^-1 ([(LSMO)₁ /(BFO)₁ ]₆₀ ) is obtained. Ab initio simulations show that due to the different magnetic domain formation energies, the magnetic moment orientation tends to be paramagnetic in the FM/AFM interface. The work focuses on the magnetic domain formation energy and provides a pathway to construct artificial heterostructures that can be an effective way to tune the magnetic moment orientation and control the magnetization of ultrathin films.

Keywords: ferromagnetic-antiferromagnetic coupling; heterointerfaces; superlattices.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.