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Spectral equivalences and symmetry breaking in integrable SU_q(N) spin chains with boundaries

A. Nichols
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Abstract

We consider the SU_q (N) invariant spin chain with diagonal and non-diagonal integrable boundary terms. The algebraic study of spin chains with different types of boundary terms is used to motivate a set of spectral equivalences between integrable chains with purely diagonal boundary terms and ones with an arbitrary non-diagonal term at one end. For each choice of diagonal boundary terms there is an isospectral one-boundary problem and vice-versa. The quantum group SU_q (N) symmetry is broken by the presence of a non-diagonal boundary term however one can use the spectral equivalence with the diagonal chain to easily understand the residual symmetries of the system.

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A. Nichols. 2005-07-21. Spectral equivalences and symmetry breaking in integrable SU_q(N) spin chains with boundaries. https://doi.org/10.1088/1742-5468%2F2005%2F09%2Fp09009

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