Anomalous helicity-dependent photocurrent in the topological insulator (Bi0.5Sb0.5)2Te3 on a GaAs substrate

被引：13

作者：

Qu, Dong-Xia ^{[1
]}

Che, Xiaoyu ^{[2
]}

Kou, Xufeng ^{[2
,3
]}

Pan, Lei ^{[2
]}

Crowhurst, Jonathan ^{[1
]}

Armstrong, Michael R. ^{[1
]}

Dubois, Jonathan ^{[1
]}

Wang, Kang L. ^{[2
]}

Chapline, George F. ^{[1
]}

机构：

[1] Lawrence Livermore Natl Lab, Livermore, CA 94550 USA

[2] Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA USA

[3] ShanghaiTech Univ, Sch Informat Sci & Technol, Shanghai 201210, Peoples R China

来源：

PHYSICAL REVIEW B | 2018年 / 97卷 / 04期

关键词：

EL2; POLARIZATION; BI2SE3; DEFECT; LEVEL;

D O I：

10.1103/PhysRevB.97.045308

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The emergingmaterial, topological insulator, has provided newopportunities for spintronic applications, owing to its strong spin-orbit character. Topological insulator based heterostructures that display spin-charge coupling driven by topology at surfaces have great potential for the realization of novel spintronic devices. Here, we report the observation of anomalous photogalvanic effect in (Bi0.5Sb0.5)(2)Te-3 thin films grown on GaAs substrate. We demonstrate that the magnitude, direction, and temperature dependence of the helicity-dependent photocurrent (HDPC) can be modulated by the gate voltage. From spatially resolved photocurrent measurements, we show that the line profile of HDPC in (Bi0.5Sb0.5)(2)Te-3/GaAs is unaffected by the variation of beam size, in contrast to the photocurrent response measured in a (Bi0.5Sb0.5)(2)Te-3/mica structure.

引用

页数：9

共 32 条

[1] The energy level of the EL2 defect in GaAs [J].