title: Unconventional superconductivity and interaction induced Fermi surface reconstruction in the two-dimensional Edwards model.
abstract: We study the competition between unconventional superconducting pairing and charge density wave (CDW) formation for the two-dimensional Edwards Hamiltonian at half filling, a very general two-dimensional transport model in which fermionic charge carriers couple to a correlated background medium. Using the projective renormalization method we find that a strong renormalization of the original fermionic band causes a new hole-like Fermi surface to emerge near the center of the Brillouin zone, before it eventually gives rise to the formation of a charge density wave. On the new, disconnected parts of the Fermi surface superconductivity is induced with a sign-changing order parameter. We discuss these findings in the light of recent experiments on iron-based oxypnictide superconductors.
authors.affiliation: IFW Dresden, P.O. Box 270116, 01171 Dresden, Germany.
authors.forename: Dai-Ning
authors.initials: DN
authors.lastname: Cho
authors.affiliation: IFW Dresden, P.O. Box 270116, 01171 Dresden, Germany.
authors.forename: Jeroen
authors.initials: J
authors.lastname: van den Brink
authors.affiliation: Institut für Physik, Ernst-Moritz-Arndt-Universität Greifswald, D-17487 Greifswald, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Fehske
authors.affiliation: Institut für Theoretische Physik, Technische Universität Dresden, D-01062 Dresden, Germany.
authors.forename: Klaus W
authors.initials: KW
authors.lastname: Becker
authors.affiliation: IFW Dresden, P.O. Box 270116, 01171 Dresden, Germany.
authors.forename: Steffen
authors.initials: S
authors.lastname: Sykora