We investigate two holes in the the t2g levels of a square-lattice Mott insulator with strong spin-orbit coupling. Exact diagonalization of a spin-orbital model valid at strong onsite interactions, but arbitrary spin-orbit coupling and crystal field is complemented by an effective triplon model (valid for strong spin-orbit coupling) and by a semiclassical variant of the model. We provide the magnetic phase diagram depending on crystal field and spin-orbit coupling, which largely agrees for the semiclassical and quantum models, as well as excitation spectra characterizing the various phases.
@article{arxiv.2103.06033,
title = {Magnetic phases for two $t_{2g}$ holes with spin-orbit coupling and crystal field},
author = {Pascal Strobel and Friedemann Aust and Maria Daghofer},
journal= {arXiv preprint arXiv:2103.06033},
year = {2021}
}