title: Mutual Independence of Critical Temperature and Superfluid Density under Pressure in Optimally Electron-Doped Superconducting LaFeAsO(1-x)F(x).
abstract: The superconducting properties of LaFeAsO(1-x)F(x) under conditions of optimal electron doping are investigated upon the application of external pressure up to ∼23  kbar. Measurements of muon-spin spectroscopy and dc magnetometry evidence a clear mutual independence between the critical temperature T(c) and the low-temperature saturation value for the ratio n(s)/m(*) (superfluid density over effective band mass of Cooper pairs). Remarkably, a dramatic increase of ∼30% is reported for n(s)/m(*) at the maximum pressure value while T(c) is substantially unaffected in the whole accessed experimental window. We argue and demonstrate that the explanation for the observed results must take the effect of nonmagnetic impurities on multiband superconductivity into account. In particular, the unique possibility to modify the ratio between intraband and interband scattering rates by acting on structural parameters while keeping the amount of chemical disorder constant is a striking result of our proposed model.
authors.affiliation: Leibniz-Institut für Festkörper- und Werkstoffforschung (IFW) Dresden, D-01171 Dresden, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Prando
authors.affiliation: Institut für Theoretische Physik III, Ruhr-Universität Bochum, D-44801 Bochum, Germany.
authors.forename: Th
authors.initials: T
authors.lastname: Hartmann
authors.affiliation: Leibniz-Institut für Festkörper- und Werkstoffforschung (IFW) Dresden, D-01171 Dresden, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Schottenhamel
authors.affiliation: Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.
authors.forename: Z
authors.initials: Z
authors.lastname: Guguchia
authors.affiliation: Dipartimento di Fisica and Unità CNISM di Pavia, Università di Pavia, I-27100 Pavia, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Sanna
authors.affiliation: Institut für Theoretische Physik III, Ruhr-Universität Bochum, D-44801 Bochum, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Ahn
authors.affiliation: Institute for Electrophysics, Russian Academy of Sciences, Ural Branch, Ekaterinburg 620016, Russian Federation.
authors.forename: I
authors.initials: I
authors.lastname: Nekrasov
authors.affiliation: Leibniz-Institut für Festkörper- und Werkstoffforschung (IFW) Dresden, D-01171 Dresden, Germany.
authors.forename: C G F
authors.initials: CG
authors.lastname: Blum
authors.affiliation: Leibniz-Institut für Festkörper- und Werkstoffforschung (IFW) Dresden, D-01171 Dresden, Germany.
authors.forename: A U B
authors.initials: AU
authors.lastname: Wolter
authors.affiliation: Leibniz-Institut für Festkörper- und Werkstoffforschung (IFW) Dresden, D-01171 Dresden, Germany.|Institut für Festkörperphysik, Technische Universität Dresden, D-01062 Dresden, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Wurmehl
authors.affiliation: Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland.
authors.forename: R
authors.initials: R
authors.lastname: Khasanov
authors.affiliation: Institut für Theoretische Physik III, Ruhr-Universität Bochum, D-44801 Bochum, Germany.|Kazan (Volga region) Federal University, 420008 Kazan, Russian Federation.
authors.forename: I
authors.initials: I
authors.lastname: Eremin
authors.affiliation: Leibniz-Institut für Festkörper- und Werkstoffforschung (IFW) Dresden, D-01171 Dresden, Germany.|Institut für Festkörperphysik, Technische Universität Dresden, D-01062 Dresden, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Büchner