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arXiv · 1206.0814

Generalized T-Q relations and the open spin-s XXZ chain with nondiagonal boundary terms

Rashad Baiyasi·Rajan Murgan
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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 s = 1 case as an example.

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Rashad Baiyasi, Rajan Murgan. 2012-10-08. Generalized T-Q relations and the open spin-s XXZ chain with nondiagonal boundary terms. https://doi.org/10.1088/1742-5468%2F2012%2F10%2Fp10003

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