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arXiv:hep-th/9504085 · Journal of Physics A Mathematical and General

Analytical Bethe ansatz for a A2n-1(2), Bn(1), Cn(1), Dn(1)quantum-algebra-invariant open spin chains

Simone Artz, Luca Mezincescu, Rafael I. Nepomechie

Published Sep 21, 1995• 42 citations
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Abstract

We determine the eigenvalues of the transfer matrices for integrable open quantum spin chains which are associated with the affine Lie algebras A 2n-1 (2) , B n (1) , C n (1) , D n (1) , and which have the quantum-algebra invariance U q (C n ), U q (B n ), U q (C n ), U q (D n ), respectively.
DOI
10.1088/0305-4470/28/18/006

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SPECTRUM OF THE TRANSFER MATRIX FOR THE Uq(Bn)-INVARIANT A2n(2)A_{2n}^{(2)}A2n(2)​ OPEN SPIN CHAIN
We propose an expression for the eigenvalues of the transfer matrix for the Uq(Bn)-invariant open quantum spin chain associated with the fundamental representation of [Formula: see text] By assumption, the Bethe ansatz equations are “doubled” with respect to those of the corresponding closed chain with periodic boundary conditions. We verify that the transfer matrix eigenvalues have the correct analyticity properties and asymptotic behavior. We also briefly discuss the structure of the eigenstates of the transfer matrix.