arXiv:1506.02147 · Nuclear Physics B

Modified algebraic Bethe ansatz for XXZ chain on the segment – III – Proof

Jean Avan, S. Belliard, Nicolas Grosjean, Rodrigo A. Pimenta

Published Aug 11, 2015• 77 citations

Abstract

In this paper, we prove the off-shell equation satisfied by the transfer matrix associated with the XXZ spin-12 chain on the segment with two generic integrable boundaries acting on the Bethe vector. The essential step is to prove that the expression of the action of a modified creation operator on the Bethe vector has an off-shell structure which results in an inhomogeneous term in the eigenvalues and Bethe equations of the corresponding transfer matrix.

DOI: 10.1016/j.nuclphysb.2015.08.006

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