HgCdTe拓扑相中的非局域太赫兹光电导性。

Non-local terahertz photoconductivity in the topological phase of HgCdTe.

作者信息

Kazakov A S, Galeeva A V, Artamkin A I, Ikonnikov A V, Ryabova L I, Dvoretsky S A, Mikhailov N N, Bannikov M I, Danilov S N, Khokhlov D R

机构信息

Physics Department, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia.

Chemistry Department, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia.

出版信息

Sci Rep. 2021 Jan 15;11(1):1587. doi: 10.1038/s41598-021-81099-6.

DOI:10.1038/s41598-021-81099-6

PMID:33452348

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7810835/

Abstract

We report on observation of strong non-local photoconducitivity induced by terahertz laser pulses in non-zero magnetic field in heterostructures based on HgCdTe films being in the topological phase. While the zero-field non-local photoconductivity is negligible, it is strongly enhanced in magnetic fields ~ 0.05 T resulting in appearance of an edge photocurrent that exceeds the respective dark signal by orders of magnitude. This photocurrent is chiral, and the chirality changes every time the magnetic field or the electric bias is reversed. Appearance of the non-local terahertz photoconductivity is attributed to features of the interface between the topological film and the trivial buffer.

摘要

我们报道了在基于处于拓扑相的碲镉汞薄膜的异质结构中，太赫兹激光脉冲在非零磁场中诱导出的强非局域光电导性的观测结果。虽然零场非局域光电导性可忽略不计，但在约0.05 T的磁场中它会显著增强，导致出现边缘光电流，该光电流比相应的暗信号高出几个数量级。这种光电流是手性的，并且每当磁场或电偏压反转时，手性就会改变。非局域太赫兹光电导性的出现归因于拓扑薄膜与平凡缓冲层之间界面的特性。