Article

Family of spin-S chain representations of SU(2)(k) Wess-Zumino-Witten models

Physical review. B, Condensed matter (Impact Factor: 3.66). 10/2011; 85(19). DOI: 10.1103/PhysRevB.85.195149
Source: arXiv

ABSTRACT We investigate a family of spin-S chain Hamiltonians recently introduced by
one of us. For S=1/2, it corresponds to the Haldane-Shastry model. For general
spin S, we find indication that the low-energy theory of these spin chains is
described by the SU(2)_k Wess-Zumino-Witten model with coupling k=2S. In
particular, we investigate the S=1 model whose ground state is given by a
Pfaffian for even number of sites N. We reconcile aspects of the spectrum of
the Hamiltonian for arbitrary N with trial states obtained by Schwinger
projection of two Haldane-Shastry chains.

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