Exact and numerical results for the dimerized spin-orbital model

M. J. Martins; B. Nienhuis

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arXiv · cond-mat/0004238

Exact and numerical results for the dimerized spin-orbital model

M. J. Martins·B. Nienhuis

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Abstract

We establish exact results for the one-dimensional spin-orbital model for special values of the four-spin interaction $V$ and dimerization parameter $δ$. The first exact result is at $δ=1/2$ and $V=-2$. Because we find a very small but finite gap in this dimerized chain, this can serve as a very strong test case for numerical and approximate analytical techniques. The second result is for the homogeneous chain with $V=-4$ and gives evidence that the system has a spontaneously dimerized ground state. Numerical results indicate that the interplay between dimerization and interaction could result in gapless phases in the regime $0\leq V<-2$.

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M. J. Martins, B. Nienhuis. 2000-04-14. Exact and numerical results for the dimerized spin-orbital model. https://arxiv.org/abs/cond-mat/0004238

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