Numerical Study of the Wheatley-Hsu-Anderson Interlayer Tunneling mechanism of High T_c Superconductivity

We present results obtained (by exact diagonalization) for the problem of two t-J planes with an interlayer coupling $t_\perp$. Our results for small hole concentrations show that in-plane superconducting correlations are enhanced by $t_\perp$. When the constraint on double occupancy in the t-J model is relaxed, the enhancement disappears. These results illustrate the inter--layer tunneling mechanism for superconductivity.