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arXiv · 1307.2023

Off-diagonal Bethe ansatz solutions of the anisotropic spin-1/2 chains with arbitrary boundary fields

Junpeng Cao·Wen-Li Yang·Kangjie Shi·Yupeng Wang
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Abstract

The anisotropic spin-1/2 chains with arbitrary boundary fields are diagonalized with the off-diagonal Bethe ansatz method. Based on the properties of the R-matrix and the K-matrices, an operator product identity of the transfer matrix is constructed at some special points of the spectral parameter. Combining with the asymptotic behavior (for XXZ case) or the quasi-periodicity properties (for XYZ case) of the transfer matrix, the extended T-Q ansatzs and the corresponding Bethe ansatz equations are derived.

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Junpeng Cao, Wen-Li Yang, Kangjie Shi, Yupeng Wang. 2013-10-27. Off-diagonal Bethe ansatz solutions of the anisotropic spin-1/2 chains with arbitrary boundary fields. https://doi.org/10.1016/j.nuclphysb.2013.10.001

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