title: Observation of interband pairing interaction in a two-band superconductor: MgB2.
abstract: The recently discovered anisotropic superconductor MgB2 is the first of its kind showing the intriguing properties of two-band superconductivity. By tunneling experiments using thin film tunnel junctions, electron-coupled phonon spectra were determined showing that superconductivity in MgB2 is phonon mediated. In a further analysis, which involves first principles calculations, the strongest feature in these spectra could be traced back to the key quantity of two-band superconductivity, the interband pairing interaction. For the phonons, this interaction turns out quite selective. It involves mainly low-energy optical phonon modes, where the boron atoms move perpendicular to the boron planes.
authors.affiliation: Forschungszentrum Karlsruhe, Institut für Festkörperphysik, P.O.B. 3640, D-76021 Karlsruhe, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Geerk
authors.forename: R
authors.initials: R
authors.lastname: Schneider
authors.forename: G
authors.initials: G
authors.lastname: Linker
authors.forename: A G
authors.initials: AG
authors.lastname: Zaitsev
authors.forename: R
authors.initials: R
authors.lastname: Heid
authors.forename: K-P
authors.initials: KP
authors.lastname: Bohnen
authors.forename: H
authors.initials: H
authors.lastname: v Löhneysen