Antiferromagnetic Magnons And Local Anisotropy: Dynamical Mean-Field Study

We present a dynamical mean-field study of antiferromagnetic magnons in a one-, two-, and three-orbital Hubbard model of square and bcc cubic lattice at intermediate coupling strength. We investigate 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 analyze a model with spin-orbit coupling in cubic site-symmetry setting. The ordered states as well as the magnetic excitations are sensitive to even a small breaking of SU(2) symmetry of the model and follow the expectations of spin-wave theory as well as general symmetry considerations.