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arXiv · 2105.12468

Antiferromagnetic magnons and local anisotropy: dynamical mean-field study

A. Niyazi·D. Geffroy·J. Kunes
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Abstract

We present a dynamical mean-field study of antiferromagnetic magnons in one-, two- and three-orbital Hubbard model of square and bcc cubic lattice at intermediate coupling strength. Weinvestigate the effect of anisotropy introduced by an external magnetic field or single-ion anisotropy.For the latter we tune continuously between the easy-axis and easy-plane models. We also analyzea model with spin-orbit coupling in cubic site-symmetry setting. The ordered states as well as themagnetic excitations are sensitive to even a small breaking ofSU(2)symmetry of the model andfollow the expectations of spin-wave theory as well as general symmetry considerations.

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A. Niyazi, D. Geffroy, J. Kunes. 2021-05-26. Antiferromagnetic magnons and local anisotropy: dynamical mean-field study. https://doi.org/10.1103/physrevb.104.075152

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