arXiv:1206.0814 · Journal of Statistical Mechanics Theory and Experiment

GeneralizedT–Qrelations and the open spin-sXXZ chain with nondiagonal boundary terms

Rashad Baiyasi, Rajan Murgan

Published Oct 4, 2012• 15 citations

Abstract

We consider the open spin- s XXZ quantum spin chain with nondiagonal boundary terms. By exploiting certain functional relations at roots of unity, we derive a generalized form of T – Q relation involving more than one independent Q ( u ), which we use to propose the Bethe-ansatz-type expressions for the eigenvalues of the transfer matrix. At most two of the boundary parameters are set to be arbitrary and the bulk anisotropy parameter has values η = iπ/2,iπ/4,.... We also provide numerical evidence for the completeness of the Bethe-ansatz-type solutions derived, using the s = 1 case as an example.

DOI: 10.1088/1742-5468/2012/10/p10003

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