Electric field controlled valley-polarized photocurrent switch based on the circular bulk photovoltaic effect
Abstract
Efficient electric manipulation of valley degrees of freedom is critical and challenging for the advancement of valley-based information science and technology. We put forth an electrical scheme, based on a two-band Dirac model, that can switch the fully valley-polarized photocurrent between K and K' valleys using the circular bulk electro-photovoltaic effect. This is accomplished by applying an out-of-plane electric field to the two-dimensional valley materials, which enables continuous tuning of the Berry curvature and its sign flip. We found that the switch of the fully valley-polarized photocurrent is directly tied to the sign change of Berry curvature, which accompanies a topological phase transition, for instance, the quantum spin Hall effect and the quantum valley Hall effect. This scheme has been confirmed in monolayer BiAsI2 and germanene through first-principles calculations. Our paper offers a promising strategy for the development of a volatile valley-addressable memory device and could inspire further research in this area.
Keywords
Cite
@article{arxiv.2406.08768,
title = {Electric field controlled valley-polarized photocurrent switch based on the circular bulk photovoltaic effect},
author = {Yaqing Yang and Xiaoyu Cheng and Liantuan Xiao and Suotang Jia and Jun Chen and Lei Zhang and Jian Wang},
journal= {arXiv preprint arXiv:2406.08768},
year = {2024}
}