0 Ju n 19 98 Studies of one - and two - hole states in the 2 D t - J model via series expansions

Studies of one-and two-hole states in the 2D t-J model via series expansions Abstract We study one and two hole properties of the t-J model at half-filling on the square lattice using series expansion methods at T = 0. The dispersion curve for one hole excitations is calculated and found to be qualitatively similar to that obtained by other methods, but the bandwidth for small t/J is some 20% larger than given previously. We also obtain the binding energy and dispersion relation for two hole bound states. The lowest bound state as t/J increases is found to be first d-wave, and then p-wave, in accordance with predictions based upon the Kohn-Luttinger effect. We also make a similar study for the t-J z model.