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Exact solution of the open XXZ chain with general integrable boundary terms at roots of unity

Rajan Murgan·Rafael I. Nepomechie·Chi Shi
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Abstract

We propose a Bethe-Ansatz-type solution of the open spin-1/2 integrable XXZ quantum spin chain with general integrable boundary terms and bulk anisotropy values i π/(p+1), where p is a positive integer. All six boundary parameters are arbitrary, and need not satisfy any constraint. The solution is in terms of generalized T - Q equations, having more than one Q function. We find numerical evidence that this solution gives the complete set of 2^N transfer matrix eigenvalues, where N is the number of spins.

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Rajan Murgan, Rafael I. Nepomechie, Chi Shi. 2006-05-22. Exact solution of the open XXZ chain with general integrable boundary terms at roots of unity. https://doi.org/10.1088/1742-5468%2F2006%2F08%2Fp08006

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