Perpendicular magnetization switching by large spin-orbit torques from sputtered Bi2Te3  

作　　者：Zhenyi Zheng Yue Zhang Daoqian Zhu Kun Zhang Xueqiang Feng Yu He Lei Chen Zhizhong Zhang Dijun Liu Youguang Zhang Pedram Khalili Amiri Weisheng Zhao 郑臻益;张悦;朱道乾;张昆;冯学强;何宇;陈磊;张志仲;刘迪军;张有光;Pedram Khalili Amiri;赵巍胜(Fert Beijing Research Institute,BDBC,School of Microelectronics,Beihang University,Beijing 100191,China;School of Electronics and Information Engineering,Beihang University,Beijing 100191,China;Department of Electrical and Computer Engineering,Northwestern University,Evanston,Illinois 60208,USA)

机构地区：[1]Fert Beijing Research Institute,BDBC,School of Microelectronics,Beihang University,Beijing 100191,China [2]School of Electronics and Information Engineering,Beihang University,Beijing 100191,China [3]Department of Electrical and Computer Engineering,Northwestern University,Evanston,Illinois 60208,USA

出　　处：《Chinese Physics B》2020年第7期215-220,共6页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.61971024 and 51901008);Young Elite Scientist Sponsorship Program by CAST(Grant No.2017QNRC001);the International Mobility Project(Grant No.B16001);National Key Technology Program of China(Grant No.2017ZX01032101);P.K.A.acknowledges support by a grant from the National Science Foundation,Division of Electrical,Communications and Cyber Systems(NSF ECCS-1853879).

摘　　要：Spin-orbit torque(SOT)effect is considered as an efficient way to switch the magnetization and can inspire various high-performance spintronic devices.Recently,topological insulators(TIs)have gained extensive attention,as they are demonstrated to maintain a large effective spin Hall angle(θeff SH),even at room temperature.However,molecular beam epitaxy(MBE),as a precise deposition method,is required to guarantee favorable surface states of TIs,which hinders the prospect of TIs towards industrial application.In this paper,we demonstrate that Bi2Te3 films grown by magnetron sputtering can provide a notable SOT effect in the heterostructure with perpendicular magnetic anisotropy CoTb ferrimagnetic alloy.By harmonic Hall measurement,a high SOT efficiency(8.7±0.9 Oe/(10^9 A/m^2))and a largeθ^eff SH(3.3±0.3)are obtained at room temperature.Besides,we also observe an ultra-low critical switching current density(9.7×10^9 A/m^2).Moreover,the low-power characteristic of the sputtered Bi2Te3 film is investigated by drawing a comparison with different sputtered SOT sources.Our work may provide an alternative to leverage chalcogenides as a realistic and efficient SOT source in future spintronic devices.

关 键 词：spin-orbit torque sputtered topological insulator FERRIMAGNET magnetization switching 

分 类 号：O469[理学—凝聚态物理]