Renormalization group of a two-dimensional patched Fermi surface

Using the renormalization group we calculate the single particle Green's function G and the momentum occupation function n(($) over bar) for a quasiparticle in a two-dimensional Fermi Surface (FS) composed of four symmetric patches with both flat and curved arcs in k-space. We show that G develops an anomalous dimension as a result of the vanishing of the quasiparticle weight at the FS. n((p) over bar) is a continuous function of (p) over bar = k(F)\(p) over right arrow-(k) over right arrow (F)\ with an infinite slope at FS for CU*2/(1 - CU*2) < 1. This result resembles a Luttinger liquid and indicates the breakdown of Fermi liquid theory in this regime.