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arXiv · 2103.06033

Magnetic phases for two $t_{2g}$ holes with spin-orbit coupling and crystal field

Pascal Strobel·Friedemann Aust·Maria Daghofer
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Abstract

We investigate two holes in the the $t_{2g}$ 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.

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Pascal Strobel, Friedemann Aust, Maria Daghofer. 2021-03-10. Magnetic phases for two $t_{2g}$ holes with spin-orbit coupling and crystal field. https://doi.org/10.1103/physrevb.104.115148

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