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Theory Of The One Dimensional SU(4) Spin-Orbital Model

P. Azaria·A. O. Gogolin·P. Lecheminant·A. A. Nersesyan
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Abstract

The one-dimensional spin-orbital model is studied by means of Abelian bosonization. We derive the low-energy effective theory which enables us to study small deviations from the SU(4) symmetric point. We show that there exists a massless region with algebraically decaying correlation functions, $\sim \cos(π/{2a_0} x) x^{-3/2}$. When entering the massive phase, the system displays an approximate SO(6) enlarged symmetry with a dimerization type of ordering consisting in alternating spin and orbital singlets.

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P. Azaria, A. O. Gogolin, P. Lecheminant, A. A. Nersesyan. 1999-03-02. Theory Of The One Dimensional SU(4) Spin-Orbital Model. https://arxiv.org/abs/cond-mat/9903047

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