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arXiv · 2001.10760

A Q-operator for open spin chains I: Baxter's TQ relation

Bart Vlaar·Robert Weston
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Abstract

We construct a Q-operator for the open XXZ Heisenberg quantum spin chain with diagonal boundary conditions and give a rigorous derivation of Baxter's TQ relation. Key roles in the theory are played by a particular infinite-dimensional solution of the reflection equation and by short exact sequences of intertwiners of the standard Borel subalgebras of $U_q(\widehat{\mathfrak{sl}_2})$. The resulting Bethe equations are the same as those arising from Sklyanin's algebraic Bethe ansatz.

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BibTeXRIS

Bart Vlaar, Robert Weston. 2020-01-29. A Q-operator for open spin chains I: Baxter's TQ relation. https://doi.org/10.1088/1751-8121/ab8854

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