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arXiv · 2608.15811

Topological Altermagnetic Insulators

Jasmin Bedow·Nitin Kaushal·Marcel Franz
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Abstract

We study the emergence of altermagnetic topological phases stabilized by Ising spin-orbit coupling in a prototypical Lieb lattice model of a correlated altermagnet. Treating the electron interactions within the Hartree-Fock and the exact diagonalization techniques, we establish the co-existence of a quantum spin Hall effect with altermagnetic spin order over a wide region of the parameter space for average electron densities of 2 and 4 per unit cell. We explore how the magnetic structure along edges influences the electronic behavior of the associated topological edge modes, demonstrating their robustness against inversion-symmetry breaking terms.

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Jasmin Bedow, Nitin Kaushal, Marcel Franz. 2026-08-16. Topological Altermagnetic Insulators. https://arxiv.org/abs/2608.15811

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