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arXiv · 1912.11497

Nested algebraic Bethe ansatz for deformed orthogonal and symplectic spin chains

Allan Gerrard·Vidas Regelskis
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Abstract

We construct exact eigenvectors and eigenvalues for $U_q(\mathfrak{sp}_{2n})$- and $U_q(\mathfrak{so}_{2n})$-symmetric closed spin chains by means of a nested algebraic Bethe ansatz method. We use a fusion procedure to construct higher-dimensional Lax operators. Our approach generalises and extends the results obtained by Reshetikhin and De Vega-Karowski. We also present a generalisation of Tarasov-Varchenko trace formula for nested Bethe vectors.

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BibTeXRIS

Allan Gerrard, Vidas Regelskis. 2019-12-24. Nested algebraic Bethe ansatz for deformed orthogonal and symplectic spin chains. https://doi.org/10.1016/j.nuclphysb.2020.115021

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