High-Temperature Quantum Anomalous Hall Effect in Buckled Honeycomb Antiferromagnets

Fuente: arXiv
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Autores principales: Hafez-Torbati, Mohsen, Uhrig, Götz S.
Formato: Preprint
Publicado: 2025
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author Hafez-Torbati, Mohsen
Uhrig, Götz S.
author_facet Hafez-Torbati, Mohsen
Uhrig, Götz S.
contents We propose Néel antiferromagnetic (AF) Mott insulators with a buckled honeycomb structure as potential candidates to host a high-temperature AF Chern insulator (AFCI). Using a generalized Kondo lattice model we show that the staggered potential induced by a perpendicular electric field due to the buckling can drive the AF Mott insulator to an AFCI phase. We address the temperature evolution of the Hall conductance and the chiral edge states. The quantization temperature $T_q$, below which the Hall conductance is quantized, depends essentially on the strength of the spin-orbit coupling and the hopping parameter, independent of the specific details of the model. The deviation of the Hall conductance from the quantized value $e^2/h$ above $T_q$ is found to be accompanied by a spectral broadening of the chiral edge states, reflecting a finite life-time, i.e., a decay. Using parameters typical for heavy transition-metal elements we predict that the AFCI can survive up to room temperature. We suggest Sr$_3$CaOs$_2$O$_9$ as a potential compound to realize a high-$T$ AFCI phase.
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id arxiv_https___arxiv_org_abs_2511_04551
institution arXiv
publishDate 2025
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spellingShingle High-Temperature Quantum Anomalous Hall Effect in Buckled Honeycomb Antiferromagnets
Hafez-Torbati, Mohsen
Uhrig, Götz S.
Strongly Correlated Electrons
We propose Néel antiferromagnetic (AF) Mott insulators with a buckled honeycomb structure as potential candidates to host a high-temperature AF Chern insulator (AFCI). Using a generalized Kondo lattice model we show that the staggered potential induced by a perpendicular electric field due to the buckling can drive the AF Mott insulator to an AFCI phase. We address the temperature evolution of the Hall conductance and the chiral edge states. The quantization temperature $T_q$, below which the Hall conductance is quantized, depends essentially on the strength of the spin-orbit coupling and the hopping parameter, independent of the specific details of the model. The deviation of the Hall conductance from the quantized value $e^2/h$ above $T_q$ is found to be accompanied by a spectral broadening of the chiral edge states, reflecting a finite life-time, i.e., a decay. Using parameters typical for heavy transition-metal elements we predict that the AFCI can survive up to room temperature. We suggest Sr$_3$CaOs$_2$O$_9$ as a potential compound to realize a high-$T$ AFCI phase.
title High-Temperature Quantum Anomalous Hall Effect in Buckled Honeycomb Antiferromagnets
topic Strongly Correlated Electrons
url https://arxiv.org/abs/2511.04551