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arXiv · 2111.04561

Bilinear-biquadratic spin-1 model in the Haldane and dimerized phases

Mykhailo V. Rakov·Michael Weyrauch
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Abstract

We study the low-lying spectrum of the bilinear-biquadratic Heisenberg model in the dimerized and Haldane phases using a tensor renormalization method. At the (Takhtajan-Babujian) critical point the finite size spectrum predicted by the Wess-Zumino-Witten (WZW) model can only partly be confirmed. We find a singlet-singlet gap which does not fit into the WZW systematics. The results obtained are compared to Bethe Ansatz, exact diagonalization, and density matrix renormalization group (DMRG) calculations for specific parameters.

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Mykhailo V. Rakov, Michael Weyrauch. 2021-11-08. Bilinear-biquadratic spin-1 model in the Haldane and dimerized phases. https://doi.org/10.1103/physrevb.105.024424

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