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

Dong Xia Qu, Xiaoyu Che, Xufeng Kou, Lei Pan, Jonathan Crowhurst, Michael R. Armstrong, Jonathan Dubois, Kang L. Wang, George F. Chapline

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)

Abstract

The emerging material, topological insulator, has provided new opportunities 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)2Te3 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)2Te3/GaAs is unaffected by the variation of beam size, in contrast to the photocurrent response measured in a (Bi0.5Sb0.5)2Te3/mica structure.

Original languageEnglish
Article number045308
JournalPhysical Review B
Volume97
Issue number4
DOIs
Publication statusPublished - 2018 Jan 24

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Anomalous helicity-dependent photocurrent in the topological insulator (Bi0.5Sb0.5) 2Te3 on a GaAs substrate'. Together they form a unique fingerprint.

Cite this