Fermionization of the spin-S Uimin-Lai-Sutherland model:: generalisation of the supersymmetric t-J model to spin-S

The spin 1 Uimin-Lai-Sutherland (ULS) isotropic chain model is expressed in terms of fermions, and the equivalence of the fermionic representation of the ULS model and the supersymmetric t-J model is established directly at the level of Hamiltonians. The spin-g ULS model is fermionized and it is shown that the model has a global sl(m/n) supersymmetry with m + n = 2S + 1. This can be regarded as spin-S generalisation of the supersymmetric t-J model. Explicit expressions for the Hamiltonian is given for S less than or equal to 7/2. (C) 2001 Elsevier Science B.V. All rights reserved.