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arXiv · 2312.16290

Altermagnetic anomalous Hall effect emerging from electronic correlations

Toshihiro Sato·Sonia Haddad·Ion Cosma Fulga·Fakher F. Assaad·Jeroen van den Brink
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Abstract

While altermagnetic materials are characterized by a vanishing net magnetic moment, their symmetry in principle allows for the existence of an anomalous Hall effect (AHE). Here we introduce a model with altermagnetism in which the emergence of an AHE is driven by interactions. This model is grounded in a modified Kane-Mele framework with antiferromagnetic (AFM) spin-spin correlations. Quantum Monte Carlo simulations show that the system undergoes a finite temperature phase transition governed by a primary AFM order parameter accompanied by a secondary one of Haldane type. The emergence of both orders turns the metallic state of the system, away from half-filling, to an altermagnet with a finite anomalous Hall conductivity. A mean field ansatz corroborates these results, which pave the way into the study of correlation induced altermagnets with finite Berry curvature.

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Toshihiro Sato, Sonia Haddad, Ion Cosma Fulga, Fakher F. Assaad, Jeroen van den Brink. 2023-12-26. Altermagnetic anomalous Hall effect emerging from electronic correlations. https://doi.org/10.1103/physrevlett.133.086503

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