title: Evidence for a vortex-glass transition in superconducting Ba(Fe0.9Co0.1)2As2.
abstract: Measurements of magneto-resistivity and magnetic susceptibility were performed on single crystals of superconducting Ba(Fe0.9Co0.1)2As2 close to the conditions of optimal doping. The high quality of the investigated samples allows us to reveal dynamic scaling behaviour associated with a vortex-glass phase transition in the limit of a weak degree of quenched disorder. Accordingly, the dissipative component of the ac susceptibility is reproduced well within the framework of Havriliak-Negami relaxation, assuming a critical power-law divergence for the characteristic correlation time τ of the vortex dynamics. Remarkably, the random disorder introduced by the Fe1-xCox chemical substitution is found to act on the vortices as a much weaker quenched disorder than previously reported for cuprate superconductors such as Y1-xPrxBa2Cu3O7-δ.
authors.affiliation: Leibniz-Institut für Festkörper- und Werkstoffforschung (IFW) Dresden, D-01171 Dresden, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Prando
authors.forename: R
authors.initials: R
authors.lastname: Giraud
authors.forename: S
authors.initials: S
authors.lastname: Aswartham
authors.forename: O
authors.initials: O
authors.lastname: Vakaliuk
authors.forename: M
authors.initials: M
authors.lastname: Abdel-Hafiez
authors.forename: C
authors.initials: C
authors.lastname: Hess
authors.forename: S
authors.initials: S
authors.lastname: Wurmehl
authors.forename: A U B
authors.initials: AU
authors.lastname: Wolter
authors.forename: B
authors.initials: B
authors.lastname: Büchner
mesh_terms: D001151:Arsenic / Q000737:chemistry*; D017609:Barium Compounds / Q000737:chemistry*; D003035:Cobalt / Q000737:chemistry*; D004553:Electric Conductivity; D005898:Glass / Q000737:chemistry*; D058085:Iron Compounds / Q000737:chemistry*; D008962:Models, Theoretical; D044367:Phase Transition
chemical_list: D017609:Barium Compounds; D058085:Iron Compounds; D003035:Cobalt; D001151:Arsenic