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arXiv · 1905.11144

Towards the solution of an integrable $D_2^{(2)}$ spin chain

Rafael I. Nepomechie·Rodrigo A. Pimenta·Ana L. Retore
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Abstract

Two branches of integrable open quantum-group invariant $D_{n+1}^{(2)}$ quantum spin chains are known. For one branch (epsilon=0), a complete Bethe ansatz solution has been proposed. However, the other branch (epsilon=1) has so far resisted solution. In an effort to address this problem, we consider here the simplest case n=1. We propose a Bethe ansatz solution, which however is not complete, as it describes only the transfer-matrix eigenvalues with odd degeneracy. We also consider a proposal for the missing eigenvalues.

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Rafael I. Nepomechie, Rodrigo A. Pimenta, Ana L. Retore. 2019-05-27. Towards the solution of an integrable $D_2^{(2)}$ spin chain. https://doi.org/10.1088/1751-8121%2Fab434d

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