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Exact SO(5) Symmetry in spin 3/2 fermionic system

Congjun Wu·Jiang-ping Hu·Shou-cheng Zhang
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Abstract

The spin 3/2 fermion models with contact interactions have a {\it generic} SO(5) symmetry without any fine-tuning of parameters. Its physical consequences are discussed in both the continuum and lattice models. A Monte-Carlo algorithm free of the sign problem at any doping and lattice topology is designed when the singlet and quintet interactions satisfy $U_0\le U_2\le -{3\over5} U_0 (U_0\le 0)$, thus making it possible to study different competing orders with high numerical accuracy. This model can be accurately realized in ultra-cold atomic systems.

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Congjun Wu, Jiang-ping Hu, Shou-cheng Zhang. 2003-08-29. Exact SO(5) Symmetry in spin 3/2 fermionic system. https://doi.org/10.1103/physrevlett.91.186402

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