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arXiv · 1409.5303

On the complete-spectrum characterization of quantum integrable spin chains via the inhomogeneous T-Q relation

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

With the XXZ spin chains as examples, we prove two theorems: (1) the functional relations derived from the off-diagonal Bethe Ansatz scheme are the sufficient and necessary conditions to characterize the complete spectrum of the corresponding transfer matrix; (2) each eigenvalue of the transfer matrix can be parameterized by a minimal inhomogeneous T-Q relation. These statements hold for both with and without inhomogeneity. The proof can be generalized to other finite-dimensional quantum integrable models.

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Junpeng Cao, Wen-Li Yang, Kangjie Shi, Yupeng Wang. 2014-09-18. On the complete-spectrum characterization of quantum integrable spin chains via the inhomogeneous T-Q relation. https://doi.org/10.1088/1751-8113/48/44/444001

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