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arXiv · 1101.2055

Multipole correlations of $t_{\rm 2g}$-orbital Hubbard model with spin-orbit coupling

Hiroaki Onishi
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Abstract

We investigate the ground-state properties of a one-dimensional $t_{\rm 2g}$-orbital Hubbard model including an atomic spin-orbit coupling by using numerical methods, such as Lanczos diagonalization and density-matrix renormalization group. As the spin-orbit coupling increases, we find a ground-state transition from a paramegnetic state to a ferromagnetic state. In the ferromagnetic state, since the spin-orbit coupling mixes spin and orbital states with complex number coefficients, an antiferro-orbital state with complex orbitals appears. According to the appearance of the complex orbital state, we observe an enhancement of $Γ_{4u}$ octupole correlations.

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Hiroaki Onishi. 2011-01-11. Multipole correlations of $t_{\rm 2g}$-orbital Hubbard model with spin-orbit coupling. https://doi.org/10.1143/jpsjs.80sa.sa141

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