Valley-related multiple Hall effect in single-layer VSi2P4

TL;DR

This paper predicts that single-layer VSi2P4 exhibits valley-related multiple Hall effects, including anomalous valley Hall and valley-polarized quantum anomalous Hall effects, driven by symmetry breaking and strain, opening new research avenues.

Contribution

It demonstrates, through first-principles calculations, the existence of valley-related multiple Hall effects in single-layer VSi2P4, a novel 2D ferromagnetic semiconductor with potential for valleytronics.

Findings

Valley-related multiple Hall effects are predicted in VSi2P4.

External strain induces band inversion and valley-polarized quantum anomalous Hall effect.

The material exhibits spontaneous valley polarization due to symmetry breaking.

Abstract

2D materials with valley-related multiple Hall effect are both fundamentally intriguing and practically appealing to explore novel phenomena and applications, but have been largely overlooked up to date. Here, using first-principles calculations, we present that valley related multiple Hall effect can exist in single-layer VSi2P4. We identify single-layer VSi2P4 as a ferromagnetic semiconductor with out-of-plane magnetization and valley physics. Arising from the joint effect of inversion symmetry breaking and time reversal symmetry breaking, the exotic spontaneous valley polarization occurs in single-layer VSi2P4, thus facilitating the observation of anomalous valley Hall effect. Moreover, under external strain, band inversion can occur at only one of the valleys of single-layer VSi2P4, enabling the long-sought valley-polarized quantum anomalous Hall effect, and meanwhile the anomalous valley Hall effect is well preserved.. Our work not only enriches the research on valley-related multiple Hall effect, but also opens a new avenue for exploring valley-polarized quantum anomalous Hall effect.