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arXiv · 2306.16466

Chiral spin liquid phase in an optical lattice at mean-field level

Jian Yang·Xiong-Jun Liu
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Abstract

We study an optical Raman square lattice with $\mathrm{U}(1)$ synthetic gauge flux to show chiral spin liquid (CSL) phase for cold atoms based on slave-rotor theory and spinon mean-field theory, respectively. An effective U($1$) gauge flux generated by Raman potentials plays a major role in realizing the CSL phase. By using slave-rotor techniques we find CSL phase at intermediate on-site Fermi Hubbard interacting regime. For the strong interacting regime we derive an effective spin model including up to the four spin interactions. By spinon mean-field analysis it is shown that CSL phase is stabilized in the case of strong magnetic frustration. The two mean-field approximation methods give consistent phase diagrams and provide qualitative numerical evidence of the CSL phase.

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Jian Yang, Xiong-Jun Liu. 2023-06-28. Chiral spin liquid phase in an optical lattice at mean-field level. https://doi.org/10.1103/physrevb.109.165108

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