抄録
We study the S matrix of a spin-{s} quantum spin chain whichcan be interpreted as a multicomponent quantum lattice gas. We showthat this system contains integrable subsystems where the Bethe ansatzmethod is applicable. We demonstrate that for some ranges ofparameters of a spin-1 model, the ground states and low-lying excitedstates are exactly given by those of integrable subsystems; exactcalculation is possible even if the system is not strictly integrableas a whole. We also analyze the magnetization curves for the spinchain, with exact saturation fields.
