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arXiv · 2208.02197

Algebraic Bethe ansatz for Q-operators of the open XXX Heisenberg chain with arbitrary spin

Rouven Frassek·István M. Szécsényi
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Abstract

In this note we construct Q-operators for the spin s open Heisenberg XXX chain with diagonal boundaries in the framework of the quantum inverse scattering method. Following the algebraic Bethe ansatz we diagonalise the introduced Q-operators using the fundamental commutation relations. By acting on Bethe off-shell states and explicitly evaluating the trace in the auxiliary space we compute the eigenvalues of the Q-operators in terms of Bethe roots and show that the unwanted terms vanish if the Bethe equations are satisfied.

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Rouven Frassek, István M. Szécsényi. 2022-08-03. Algebraic Bethe ansatz for Q-operators of the open XXX Heisenberg chain with arbitrary spin. https://doi.org/10.1088/1751-8121%2Faca5d3

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