title: Soft fermi surfaces and breakdown of Fermi-liquid behavior.
abstract: Electron-electron interactions can induce Fermi surface deformations which break the point-group symmetry of the lattice structure of the system. In the vicinity of such a "Pomeranchuk instability" the Fermi surface is easily deformed by anisotropic perturbations, and exhibits enhanced collective fluctuations. We show that critical Fermi surface fluctuations near a d-wave Pomeranchuk instability in two dimensions lead to large anisotropic decay rates for single-particle excitations, which destroy Fermi-liquid behavior over the whole surface except at the Brillouin zone diagonal.
authors.affiliation: Max-Planck-Institut für Festkörperforschung, D-70569 Stuttgart, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Metzner
authors.forename: D
authors.initials: D
authors.lastname: Rohe
authors.forename: S
authors.initials: S
authors.lastname: Andergassen