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arXiv · 2502.10055

Multifunctional Altermagnet with Large Out-of-Plane Piezoelectric Response in Janus V$_{2}$AsBrO Monolayer

Qiuyue Ma·Busheng Wang·Guochun Yang·Yong Liu
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Abstract

Altermagnetism has emerged as a third fundamental category of collinear magnetism, characterized by spin-splitting in symmetry-compensated collinear antiferromagnets, opening new frontiers in spintronics and condensed matter physics. Here, based on first-principles calculations, we propose a novel altermagnetic semiconductor, the asymmetric Janus V$_2$AsBrO monolayer, which exhibits a magnetic easy axis favoring the out-of-plane direction and a Néel temperature ($T_N$) exceeding room temperature. The system exhibits a strain-tunable piezovalley effect, generating valley polarization under uniaxial strain. Notably, hole doping under uniaxial strain generates a net magnetization ($M$) through a piezomagnetic mechanism. Additionally, the broken inversion symmetry endows the monolayer with a substantial out-of-plane piezoelectric coefficient $d_{31}$ (2.19 pm/V), presenting broad prospects for the development and design of novel piezoelectric devices. Our findings provide a promising candidate material for the advancement of 2D multifunctional devices in nanoelectronics, spintronics, valleytronics, and piezoelectrics.

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Qiuyue Ma, Busheng Wang, Guochun Yang, Yong Liu. 2025-02-19. Multifunctional Altermagnet with Large Out-of-Plane Piezoelectric Response in Janus V$_{2}$AsBrO Monolayer. https://arxiv.org/abs/2502.10055

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