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arXiv · 1401.4523

Axionic Antiferromagnetic Insulator Phase in a Correlated and Spin-Orbit Coupled System

Akihiko Sekine·Kentaro Nomura
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Abstract

We study theoretically a three-dimensional correlated and spin-orbit coupled system, the half-filled extended Fu-Kane-Mele-Hubbard model on a diamond lattice, focusing on the topological magnetoelectric response of the antiferromagnetic insulator phase. In the antiferromagnetic insulator phase, the Dirac-like low-energy effective Hamiltonian is obtained. Then the theta term, which results in the magnetoelectric response, is derived as a consequence of the chiral anomaly. The realization of the dynamical axion field in our model is discussed. The relation with a symmetry broken phase induced by interactions in lattice quantum chromodynamics is also discussed.

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Akihiko Sekine, Kentaro Nomura. 2014-01-18. Axionic Antiferromagnetic Insulator Phase in a Correlated and Spin-Orbit Coupled System. https://doi.org/10.7566/jpsj.83.104709

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