HOLE-HOLE CONTACT INTERACTION IN THE T-J MODEL

Using a variational approach we calculate the hole-hole contact interaction on the quantum Neel background. Explicit analytical expressions for the vertex function of the interaction are obtained. Solution of the Bethe-Salpeter equation with this interaction gives bound states in d and p waves with binding energies close to those obtained recently by numerical methods. At t/J greater-than-or-equal-to 2-3 the bound state disappears.