Numerical evidence for electron decay in the two-dimensional t-J model

A variety of computational results on the t-J model is reviewed and the case made that they constitute evidence for the decay of quasiparticles into other, more open-quotes elementaryclose quotes particles at low energy scales in doping range relevant to high-Tc superconductivity. At low dopings these particles bind together with a linear potential associated with the underlying magnetic order to form a sharp quasiparticle. At higher dopings the order disappears, and the quasiparticle becomes a scattering resonance. A brief review of the Bethe solution of the t-J model in 1 dimension is also made and a numerical argument presented that the particles in question are 2-dimensional analogues of spinons and holons. Some elementary calculations using these particles as the fundamental degrees of freedom reviewed and shown to account simply for several strange features of the numerical results. Both variational and gauge theory calculations are considered