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SU(4) Spin-Orbital Two-Leg Ladder, Square and Triangle Lattices

Shun-Qing Shen
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Abstract

Based on the generalized valence bond picture, a Schwinger boson mean field theory is applied to the symmetric SU(4) spin-orbital systems. For a two-leg SU(4) ladder, the ground state is a spin-orbital liquid with a finite energy gap, in good agreement with recent numerical calculations. In two-dimensional square and triangle lattices, the SU(4) Schwinger bosons condense at (π/2,π/2) and (π/3,π/3), respectively. Spin, orbital, and coupled spin-orbital static susceptibilities become singular at the wave vectors, twice of which the bose condensation arises at. It is also demonstrated that there are spin, orbital, and coupled spin-orbital long-range orderings in the ground state.

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Shun-Qing Shen. 2002-11-05. SU(4) Spin-Orbital Two-Leg Ladder, Square and Triangle Lattices. https://doi.org/10.1103/physrevb.66.214516

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