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arXiv · 2501.05702

Unconventional enhancement of anomalous Hall effect by tilt of Zeeman field in topologically-nontrivial MXenes, $M_2M'$C$_2$O$_2$

Abstract

In this paper, the anomalous Hall effect of topologically-nontrivial MXenes, $M_2M'$C$_2$O$_2$, and the electronic structure in the presence of magnetic proximity effect is theoretically investigated. The theoretical analysis is performed in two different ways: an effective model and a multi-orbital tight-binding model generated from the first-principles band structure. These two theoretical methods provided the similar profile of Berry curvature for electronic states near the bulk band gap, and they show an unconventional rise of hollowed-out peak in the profile with the tilt of proximity magnetic potential. The anomalous Hall conductivity is also calculated as a function of the charge density and the tilt angle of proximity magnetic order. Then, an unconventional enhancement of anomalous Hall conductivity by the tilt of magnetic order is theoretically predicted as a result of the variation of Berry curvature.

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Tetsuro Habe. 2025-01-10. Unconventional enhancement of anomalous Hall effect by tilt of Zeeman field in topologically-nontrivial MXenes, $M_2M'$C$_2$O$_2$. https://doi.org/10.1103/physrevb.111.035303

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