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arXiv · 1805.10144

New D_{n+1}^(2) K-matrices with quantum group symmetry

Rafael I. Nepomechie·Rodrigo A. Pimenta
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Abstract

We find new families of solutions of the $D_{n+1}^{(2)}$ boundary Yang-Baxter equation. The open spin-chain transfer matrices constructed with these K-matrices have quantum group symmetry corresponding to removing one node from the $D_{n+1}^{(2)}$ Dynkin diagram, namely, $U_{q}(B_{n-p}) \otimes U_{q}(B_{p})$, where $p=0, \ldots, n$. These transfer matrices also have a $p \leftrightarrow n-p$ duality symmetry. These symmetries help to account for the degeneracies in the spectrum of the transfer matrix.

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Rafael I. Nepomechie, Rodrigo A. Pimenta. 2018-05-24. New D_{n+1}^(2) K-matrices with quantum group symmetry. https://doi.org/10.1088/1751-8121%2Faad957

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