title: Disorder-induced gap in the normal density of states of the organic superconductor κ-(BEDT-TTF)2Cu[N(CN)2]Br.
abstract: The local density of states (DOS) of the organic superconductor κ-(BEDT-TTF)2Cu[N(CN)2]Br, measured by scanning tunneling spectroscopy on in situ cleaved surfaces, reveals a logarithmic suppression near the Fermi edge persisting above the critical temperature T(c). The experimentally observed suppression of the DOS is in excellent agreement with a soft Hubbard gap as predicted by the Anderson-Hubbard model for systems with disorder. The electronic disorder also explains the diminished coherence peaks of the quasi-particle DOS below T(c).
authors.affiliation: Graduate School Materials Science In Mainz, Staudingerweg 9, 55128 Mainz, Germany. Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudingerweg 7, 55128 Mainz, Germany.
authors.forename: Sandra
authors.initials: S
authors.lastname: Diehl
authors.forename: Torsten
authors.initials: T
authors.lastname: Methfessel
authors.forename: Ulrich
authors.initials: U
authors.lastname: Tutsch
authors.forename: Jens
authors.initials: J
authors.lastname: Müller
authors.forename: Michael
authors.initials: M
authors.lastname: Lang
authors.forename: Michael
authors.initials: M
authors.lastname: Huth
authors.forename: Martin
authors.initials: M
authors.lastname: Jourdan
authors.forename: Hans-Joachim
authors.initials: HJ
authors.lastname: Elmers