ENHANCED D(X(2)-Y(2)) PAIRING CORRELATIONS IN THE 2-LEG HUBBARD LADDER

The two-leg Hubbard ladder is characterized by the ratio of the inter- to intra-leg hopping t(perpendicular to)/t, the relative interaction s trength U/t, and the electron filling. Here, using density matrix reno rmalization group and Monte Carlo simulations, we examine the dependen ce of the pairing correlations on these parameters. We find that the p airing correlations are enhanced when the top of the bonding quasipart icle band and the bottom of the antibonding band are near the Fermi le vel. We present results on the single-particle spectral weight and the antiferromagnetic correlations in order to explain this behavior.