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Looking at the Haldane Conjecture from a Grouptheoretical Point of View

K. -H. Mütter
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Abstract

Based on the Lieb-Schultz-Mattis construction we present a five parameter family of Spin-1 Hamiltonians with degenerate groundstate. Starting from the critical $SU(3)$ symmetric Hamiltonian, we look for those perturbations of the $SU(3)$ symmetry, which leave the groundstate degenerate. We also discuss the spin-3/2 $SU(4)$-case.

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K. -H. Mütter. 1994-03-03. Looking at the Haldane Conjecture from a Grouptheoretical Point of View. https://doi.org/10.1007/bf01313021

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