1 August 2000, 2 p.m.

Dr. Thomas Pruschke
(Regensburg)
The Dynamical Cluster Approximation: Non-Local Correlations in the 2D Hubbard-Model

Abstract:
A new approximate technique to study correlated electron systems is presented that maps the lattice problem onto a cluster model embedded in a self-consistent bath. The method is manifestly causal and can be viewed as complementary to standard finite size calculations. Results for the influence of nonlocal dynamical fluctuations on the physics of the 2D Hubbard model are presented and the existence of d-wave superconductivity in the intermediate and strong coupling limit discussed.