Electric-field-tuned anomalous valley Hall effect in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>A</mml:mi></mml:math>-type hexagonal antiferromagnetic monolayers
San‐Dong Guo, Yu-Ling Tao, Zi-Yang Zhuo, Gangqiang Zhu, Yee Sin Ang
Abstract
The combination of antiferromagnetic (AFM) spintronics and anomalous valley Hall effect (AVHE) is of great significance for potential applications in valleytronics. Here, we propose a way for achieving AVHE in $A$-type hexagonal AFM monolayer. The proposed way involves the introduction of layer-dependent electrostatic potential caused by an out-of-plane external electric field, which can break the combined symmetry ($PT$ symmetry) of spatial inversion ($P$) and time reversal ($T$), producing spin splitting. The spin order of spin splitting can be reversed by regulating the direction of electric field. Based on first-principles calculations, the way can be verified in AFM ${\mathrm{Cr}}_{2}{\mathrm{CH}}_{2}$. The layer-locked hidden Berry curvature can give rise to layer-Hall effect, including a valley layer--spin Hall effect and layer-locked AVHE. Moreover, we propose Janus monolayer ${\mathrm{Cr}}_{2}\mathrm{CHF}$ with internal electric polarization, which can also realize the AVHE. Our works provide an experimentally feasible way to realize AVHE in AFM monolayer.