Proximity-Induced Magnetic Order in a Transferred Topological Insulator Thin Film on a Magnetic Insulator

Xiaoyu Che; Koichi Murata; Lei Pan; Qing Lin He; Guoqiang Yu; Qiming Shao; Gen Yin; Peng Deng; Yabin Fan; Bo Ma; Xiao Liang; Bin Zhang; Xiaodong Han; Lei Bi; Qing-Hui Yang; Huaiwu Zhang; Kang L Wang

doi:10.1021/acsnano.8b02647

Proximity-Induced Magnetic Order in a Transferred Topological Insulator Thin Film on a Magnetic Insulator

ACS Nano. 2018 May 22;12(5):5042-5050. doi: 10.1021/acsnano.8b02647. Epub 2018 May 11.

Authors

Xiaoyu Che¹, Koichi Murata¹, Lei Pan¹, Qing Lin He¹, Guoqiang Yu^{1

2}, Qiming Shao¹, Gen Yin¹, Peng Deng¹, Yabin Fan¹, Bo Ma³, Xiao Liang⁴, Bin Zhang⁵, Xiaodong Han⁵, Lei Bi⁴, Qing-Hui Yang³, Huaiwu Zhang³, Kang L Wang^{1

6}

Affiliations

¹ Department of Electrical and Computer Engineering , University of California , Los Angeles , California 90095 , United States.
² Beijing National Laboratory for Condensed Matter Physics , Institute of Physics, Chinese Academy of Sciences , Beijing 100190 , China.
³ State Key Laboratory of Electronic Thin Film and Integrated Devices , University of Electronic Science and Technology of China , Chengdu 610054 , China.
⁴ National Engineering Research Center of Electromagnetic Radiation Control Materials , University of Electronic Science and Technology of China , Chengdu 610054 , China.
⁵ Beijing Key Lab of Microstructure and Property of Advanced Materials , Beijing University of Technology , Beijing 100124 , China.
⁶ Department of Materials Science and Engineering , University of California , Los Angeles , California 90095 , United States.

PMID: 29733577
DOI: 10.1021/acsnano.8b02647

Abstract

Breaking the time reversal symmetry (TRS) in a topological insulator (TI) by introducing a magnetic order gives rise to exotic quantum phenomena. One of the promising routes to inducing a magnetic order in a TI is utilizing magnetic proximity effect between a TI and a strong magnetic insulator (MI). In this article, we demonstrate a TI/MI heterostructure prepared through transferring a molecular beam epitaxy (MBE)-grown Bi₂Se₃ film onto a yttrium iron garnet (YIG) substrate via wet transfer. The transferred Bi₂Se₃ exhibits excellent quality over a large scale. Moreover, through wet transfer we are able to engineer the interface and perform a comparative study to probe the proximity coupling between Bi₂Se₃ and YIG under different interface conditions. A detailed investigation of both the anomalous Hall effect and quantum corrections to the conductivity in magnetotransport measurements reveals an induced magnetic order as well as TRS breaking in the transferred Bi₂Se₃ film on YIG. In contrast, a thin layer of AlO _x at the interface obstructs the proximity coupling and preserves the TRS, indicating the critical role of the interface in mediating magnetic proximity effect.

Keywords: interface; magnetic insulator; magnetic proximity effect; quantum interference; topological insulator; wet transfer.

Publication types

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