arXiv:1912.11497 · Nuclear Physics B

Nested algebraic Bethe ansatz for deformed orthogonal and symplectic spin chains

Allan John Gerrard, Vidas Regelskis

Published Apr 20, 2020• 13 citations

Abstract

We construct exact eigenvectors and eigenvalues for Uq(sp2n)- and Uq(so2n)-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.

DOI: 10.1016/j.nuclphysb.2020.115021

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