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arXiv · 1607.05196

J-freezing and Hund's rules in spin-orbit-coupled multiorbital Hubbard models

Aaram J. Kim·Harald O. Jeschke·Philipp Werner·Roser Valentí
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Abstract

We investigate the phase diagram of the spin-orbit-coupled three orbital Hubbard model at arbitrary filling by means of dynamical mean-field theory combined with continuous-time quantum Monte Carlo. We find that the spin-freezing crossover occurring in the metallic phase of the non-relativistic multiorbital Hubbard model can be generalized to a $\mathbf{J}$-freezing crossover, with $\mathbf{J}=\mathbf{L}+\mathbf{S}$, in the spin-orbit-coupled case. In the $\mathbf{J}$-frozen regime the correlated electrons exhibit a non-trivial flavor selectivity and energy dependence. Furthermore, in the regions near $n=2$ and $n=4$ the metallic states are qualitatively different from each other, which reflects the atomic Hund's third rule. Finally, we explore the appearance of magnetic order from exciton condensation at $n=4$ and discuss the relevance of our results for real materials.

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Aaram J. Kim, Harald O. Jeschke, Philipp Werner, Roser Valentí. 2017-02-24. J-freezing and Hund's rules in spin-orbit-coupled multiorbital Hubbard models. https://doi.org/10.1103/physrevlett.118.086401

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