Valley-related multiple Hall effect in monolayer <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi mathvariant="normal">V</mml:mi><mml:msub><mml:mi>Si</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi mathvariant="normal">P</mml:mi><mml:mn>4</mml:mn></mml:msub></mml:mrow></mml:math>
Xiangyu Feng, Xilong Xu, Zhonglin He, Rui Peng, Ying Dai, Baibiao Huang, Yandong Ma
Abstract
Two-dimensional materials with valley-related multiple Hall effect are both fundamentally intriguing and practically appealing for exploring novel phenomena and applications, but have been largely overlooked to date. Here, using first-principles calculations, we show that the valley-related multiple Hall effect can exist in single-layer $\mathrm{V}{\mathrm{Si}}_{2}{\mathrm{P}}_{4}$. We identify single-layer $\mathrm{V}{\mathrm{Si}}_{2}{\mathrm{P}}_{4}$ 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 $\mathrm{V}{\mathrm{Si}}_{2}{\mathrm{P}}_{4}$, 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 $\mathrm{V}{\mathrm{Si}}_{2}{\mathrm{P}}_{4}$, 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 provides an ideal platform for exploring valley-polarized quantum anomalous Hall effect.