UNIFORM MAGNETIC-SUSCEPTIBILITY OF THE T-J MODEL ON THE 4X4 LATTICE

We study the temperature and doping dependence of the uniform susceptibility, chi, for the t-J model by calculating exactly the low-lying states of the 4X4 system with periodic boundary conditions. We find that at low doping and temperatures around J/3 the susceptibility increases with doping. Furthermore the peak in its temperature dependence shifts to lower temperatures with doping. These features are in agreement with high-temperature expansions. At higher dopings (6 holes or larger) the susceptibility begins to decrease with increasing doping, again consistent with high-temperature expansions.