arXiv:1408.4840 · Nuclear Physics B

Modified algebraic Bethe ansatz for XXZ chain on the segment – I: Triangular cases

S. Belliard

Published Jan 8, 2015• 90 citations

Abstract

The modified algebraic Bethe ansatz, introduced by Crampé and the author [8], is used to characterize the spectral problem of the Heisenberg XXZ spin-12 chain on the segment with lower and upper triangular boundaries. The eigenvalues and the eigenvectors are conjectured. They are characterized by a set of Bethe roots with cardinality equal to N the length of the chain and which satisfies a set of Bethe equations with an additional term. The conjecture follows from exact results for small chains. We also present a factorized formula for the Bethe vectors of the Heisenberg XXZ spin-12 chain on the segment with two upper triangular boundaries.

DOI: 10.1016/j.nuclphysb.2015.01.003

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