Author(s): Chen, SZ (Chen, Shenzhong); Yu, JL (Yu, Jinling); Zhu, KJ (Zhu, Kejing); Zeng, XL (Zeng, Xiaolin); Chen, YH (Chen, Yonghai); Liu, Y (Liu, Yu); Zhang, Y (Zhang, Yang); Cheng, SY (Cheng, Shuying); He, K (He, Ke)

Source: JOURNAL OF APPLIED PHYSICS Volume: 130 Issue: 8 Article Number: 085305 DOI: 10.1063/5.0058706 Published: AUG 28 2021

Abstract: A hallmark signature of the three-dimensional (3D) topological insulator (TI) is that the spin-momentum locked massless Dirac fermions populate its surface states, where the carrier spins are locked to their momentum. Here, we report on the magnetic-field induced helicity dependent photogalvanic effect (MHPGE) of 3D TI thin films Bi2Te3 or (BixSb1-x)(2)Te-3 of different thicknesses excited by near-infrared (1064 nm) under an in-plane magnetic field. It is found that the MHPGE current J(cx) under the longitudinal geometry, i.e., J(cx) parallel to B-x, is induced by the Larmor procession, while that under the transverse geometry, i.e., J(cx) parallel to B-y, is mainly introduced by the hexagonal warping, which can be enhanced by the in-plane magnetic field. Our work demonstrates the possibility to tune the spin-polarized photocurrent of the surface states in 3D TIs via a magnetic field, which may be utilized to design new kinds of opto-spintronic devices. Published under an exclusive license by AIP Publishing.

Accession Number: WOS:000694997000002

ISSN: 0021-8979

eISSN: 1089-7550

Full Text: https://aip.scitation.org/doi/10.1063/5.0058706