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arXiv · 1005.2723

SU(2) symmetry in a Hubbard model with spin-orbit coupling

X. Z. Zhang·L. Jin·Z. Song
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Abstract

We study the underlying symmetry in a spin-orbit coupled tight-binding model with Hubbard interaction. It is shown that, in the absence of the on-site interaction, the system possesses the SU(2) symmetry arising from the timereversal symmetry. The influence of the on-site interaction on the symmetry depends on the topology of the networks: The SU(2) symmetry is shown to be the spin rotation symmetry of a simply-connected lattice, so it still holds in the presence of the Hubbard correlation. In contrary, the on-site interaction breaks the SU(2) symmetry of a multi-connected lattice.

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X. Z. Zhang, L. Jin, Z. Song. 2010-05-16. SU(2) symmetry in a Hubbard model with spin-orbit coupling. https://doi.org/10.1007/s11433-014-5500-7

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