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arXiv · 2608.24408

Altermagnetic Anomalous Hall Effect and Spin--Edge-Locked Chiral Modes in a Modified Kane--Mele--Hubbard Model

Mohsen Hafez-Torbati·Alireza Qaiumzadeh
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Abstract

We establish a correlation-driven route to the altermagnetic anomalous Hall effect (AHE) and its associated \emph{spin--edge-locked} edge states in a modified Kane--Mele--Hubbard model. Using dynamical mean-field theory (DMFT), we show that, at half-filling, increasing the Hubbard interaction drives the system from a metallic paramagnetic phase hosting antichiral edge states into an insulating in-plane N\'eel-type antiferromagnetic phase, in which a residual antiunitary symmetry forbids the AHE. Hole doping induces a spin-flop transition to an out-of-plane N\'eel-type antiferromagnetic phase, thereby breaking this symmetry and generating a finite anomalous Hall conductivity that persists into the strongly correlated regime. Distinct from a conventional spin-polarized Hall response in ferromagnets, the altermagnetic AHE receives equal and additive contributions from the two symmetry-related spin sectors and is accompanied by spin--edge-locked chiral states. Our results demonstrate that carrier doping and spin-rotationally invariant Hubbard interactions are sufficient to realize the altermagnetic AHE, without invoking an explicitly Ising-like interaction, and provide a realistic microscopic route toward its realization in correlated transition metal dichalcogenides monolayers.

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Mohsen Hafez-Torbati, Alireza Qaiumzadeh. 2026-08-25. Altermagnetic Anomalous Hall Effect and Spin--Edge-Locked Chiral Modes in a Modified Kane--Mele--Hubbard Model. https://arxiv.org/abs/2608.24408

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