Anomalous Self-Energy Features in the 2D Hubbard Model

Abstract

The electronic self-energy of the two-dimensional Hubbard model, computed in the non-crossing approximation within the composite operator method, is studied as a function of frequency as well as temperature at the Fermi surface, for a value of doping at which the pseudogap is already well developed. For values of momentum belonging to the phantom arc of the Fermi surface, both dependences show anomalous power law behavior in contrast to that expected from the Fermi liquid theory.