Regensburg 2016 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

TT: Fachverband Tiefe Temperaturen

TT 14: Superconductivity: (General) Theory

TT 14.10: Vortrag

Montag, 7. März 2016, 17:45–18:00, H19

Unconventional superconductivity and interaction induced Fermi surface reconstruction in the two-dimensional Edwards model — •Dai-Ning Cho¹, Jeroen van den Brink¹, Holger Fehske², Klaus W. Becker³, and Steffen Sykora¹ — ¹IFW Dresden, P.O. Box 270116, D-01171 Dresden, Germany — ²Institut für Physik, Ernst-Moritz-Arndt-Universität Greifswald, D-17487 Greifswald, Germany — ³Institut für Theoretische Physik, Technische Universität Dresden, D-01062 Dresden, Germany

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 nearby 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.