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Auxiliary matrices for the six-vertex model and the algebraic Bethe ansatz

Christian Korff
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Abstract

We connect two alternative concepts of solving integrable models, Baxter's method of auxiliary matrices (or Q-operators) and the algebraic Bethe ansatz. The main steps of the calculation are performed in a general setting and a formula for the Bethe eigenvalues of the Q-operator is derived. A proof is given for states which contain up to three Bethe roots. Further evidence is provided by relating the findings to the six-vertex fusion hierarchy. For the XXZ spin-chain we analyze the cases when the deformation parameter of the underlying quantum group is evaluated both at and away from a root of unity.

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Christian Korff. 2004-04-10. Auxiliary matrices for the six-vertex model and the algebraic Bethe ansatz. https://doi.org/10.1088/0305-4470/37/29/005

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