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arXiv · 2609.33026

Piezo-Hall effect in $\mathrm{RbCr_2Se_2O}$

San-Dong Guo·Shi-Hao Zhang·Feng-Ren Fan
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Abstract

The anomalous Hall effect (AHE) is of fundamental importance for understanding spin-orbit coupling and magnetic transport in magnetic materials. Meanwhile, strain can significantly modify material properties, and the piezoelectric effect stands as a well-known representative. The piezo-Hall effect combines the two physical ingredients of AHE and strain. Specifically, the piezo-Hall effect describes a physical process in which the magnetic space group (MSG) of a magnetic material prohibits a net magnetic moment and suppresses the AHE in the pristine state but transforms into a new MSG upon strain application that permits a net magnetic moment, thereby enabling the emergence of the AHE. The underlying mechanisms cover strain-induced magnetic electronic state transition and strain tuning of magnetization direction. We take the $d$-wave altermagnetic metal as an example to analyze the piezo-Hall effect in detail, with first-principles calculations carried out on the specific material $\mathrm{RbCr_2Se_2O}$ to verify this scenario. A notable result is that under identical uniaxial strain applied along the $x$ and $y$ directions, the anomalous Hall conductivity exhibits opposite signs but equal magnitudes. Similarly, the piezo-magneto-optical effect can also be proposed, and if strain tuning is replaced by electric-field modulation, the electro-Hall effect and electro-magneto-optical effect can be also put forward accordingly. Even temperature can serve as an external field to introduce the temperature Hall effect. Our work advances the understanding of the coupling between strain and physical properties.

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San-Dong Guo, Shi-Hao Zhang, Feng-Ren Fan. 2026-09-26. Piezo-Hall effect in $\mathrm{RbCr_2Se_2O}$. https://arxiv.org/abs/2609.33026

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