q-deformations of quantum spin chains with exact valence-bond ground states
Abstract
Quantum spin chains with exact valence-bond ground states are of great interest in condensed-matter physics. A class of such models was proposed by Affleck et al., each of which is su(2)-invariant and constructed as a sum of projectors onto definite total spin states at neighbouring sites. We propose to use the machinery of the q-deformation of su(2) to obtain generalisations of such models, and work out explicitly the two simplest examples. In one case we recover the known anisotropic spin-1 VBS model while in the other we obtain a new anisotropic generalisation of the spin-1/2 Majumdar-Ghosh model.
Cite
@article{arxiv.cond-mat/9403080,
title = {q-deformations of quantum spin chains with exact valence-bond ground states},
author = {M. T. Batchelor and C. M. Yung},
journal= {arXiv preprint arXiv:cond-mat/9403080},
year = {2009}
}
Comments
9 pages, LaTeX, MRR-011-94 This paper has been expanded to include a discussion of the ground state correlations and the gap to excitations in the q-deformed generalisation of the Majumdar-Ghosh model