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arXiv · 1804.08974

Exact density matrix for quantum group invariant sector of XXZ model

Fedor Smirnov
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Abstract

Using the fermionic basis we obtain the expectation values of all $U_q(\slt)$-invariant local operators on 8 sites for the anisotropic six-vertex model on a cylinder with generic Matsubara data. In the case when the $U_q(\slt)$ symmetry is not broken this computation is equivalent to finding the entire density matrix up to 8 sites. As application, we compute the entanglement entropy without and with temperature, and compare the results with CFT predictions.

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Fedor Smirnov. 2018-04-24. Exact density matrix for quantum group invariant sector of XXZ model. https://arxiv.org/abs/1804.08974

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