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arXiv · 1909.12123

Nested algebraic Bethe ansatz for orthogonal and symplectic open spin chains

Allan Gerrard·Vidas Regelskis
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Abstract

We present a nested algebraic Bethe ansatz for one-dimensional open so(2n)- and sp(2n)-symmetric spin chains with diagonal boundary conditions and described by the extended twisted Yangian. We use a generalization of the Bethe ansatz introduced by De Vega and Karowski which allows us to relate the spectral problem of a so(2n)- or sp(2n)-symmetric open spin chain to that of a gl(n)-symmetric open spin chain. We explicitly derive the structure of Bethe vectors and the nested Bethe equations.

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Allan Gerrard, Vidas Regelskis. 2019-09-26. Nested algebraic Bethe ansatz for orthogonal and symplectic open spin chains. https://doi.org/10.1016/j.nuclphysb.2019.114909

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