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arXiv:hep-th/9302140 · Journal of Physics A Mathematical and General

Exact solution of the deformed biquadratic spin-1 chain

R. Köberle, A. Lima-Santos

Published Aug 21, 1994• 14 citations
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Abstract

We solve for the spectrum of the deformed biquadratic spin-1 chain by a generalization of the coordinate Bethe ansatz. The model is invariant under the quantum group U q sl(2) and, depending on the deformation parameter q, it's Hamiltonian may not be Hermitian. We consider several boundary conditions and find in particular that for periodic ones, the complete spectrum of the spin- 1/2 XXZ model is always contained in the spectrum of the biquadratic model. For free boundary conditions the spectrum is identical to the XXZ model spectrum, only the multiplicities are, of course, different. Bethe states are highest-weight states of the quantum group, except possibly for zero-energy states.

DOI
10.1088/0305-4470/27/16/009

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