Manipulating valley-dependent Berry phase effects provides remarkable opportunities for both fundamental research and practical applications. Here, by referring to effective model analysis, we propose a general scheme for realizing topological magneto-valley phase transitions. More importantly, by using valley-half-semiconducting VSi2N4 as an outstanding example, we investigate sign change of valley-dependent Berry phase effects which drive the change-in-sign valley anomalous transport characteristics via external means such as biaxial strain, electric field, and correlation effects. As a result, this gives rise to quantized versions of valley anomalous transport phenomena. Our findings not only uncover a general framework to control valley degree of freedom, but also motivate further research in the direction of multifunctional quantum devices in valleytronics and spintronics.
@article{arxiv.2106.06379,
title = {Sign-reversible valley-dependent Berry phase effects in 2D valley-half-semiconductors},
author = {Xiaodong Zhou and Run-Wu Zhang and Zeying Zhang and Wanxiang Feng and Yuriy Mokrousov and Yugui Yao},
journal= {arXiv preprint arXiv:2106.06379},
year = {2021}
}