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arXiv · 1504.04501

Algebraic Bethe ansatz for Q-operators: The Heisenberg spin chain

Rouven Frassek
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Abstract

We diagonalize Q-operators for rational homogeneous sl(2)-invariant Heisenberg spin chains using the algebraic Bethe ansatz. After deriving the fundamental commutation relations relevant for this case from the Yang-Baxter equation we demonstrate that the Q-operators act diagonally on the Bethe vectors if the Bethe equations are satisfied. In this way we provide a direct proof that the eigenvalues of the Q-operators studied here are given by Baxter's Q-functions.

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Rouven Frassek. 2015-04-17. Algebraic Bethe ansatz for Q-operators: The Heisenberg spin chain. https://arxiv.org/abs/1504.04501

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