title: Unpaired electrons in the heavy-fermion superconductor CeCoIn5.
abstract: Thermal conductivity and specific heat were measured in the superconducting state of the heavy-fermion material Ce(1-x)La(x)CoIn5. With increasing impurity concentration x, the suppression of T(c) is accompanied by the increase in residual electronic specific heat expected of a d-wave superconductor, but it occurs in parallel with a decrease in residual electronic thermal conductivity. This contrasting behavior reveals the presence of uncondensed electrons coexisting with nodal quasiparticles. An extreme multiband scenario is proposed, with a d-wave superconducting gap on the heavy-electron sheets of the Fermi surface and a negligible gap on the light, three-dimensional pockets.
authors.affiliation: Department of Physics, University of Toronto, Toronto, Ontario, Canada. tanatar@ims.ac.jp
authors.forename: M A
authors.initials: MA
authors.lastname: Tanatar
authors.forename: Johnpierre
authors.initials: J
authors.lastname: Paglione
authors.forename: S
authors.initials: S
authors.lastname: Nakatsuji
authors.forename: D G
authors.initials: DG
authors.lastname: Hawthorn
authors.forename: E
authors.initials: E
authors.lastname: Boaknin
authors.forename: R W
authors.initials: RW
authors.lastname: Hill
authors.forename: F
authors.initials: F
authors.lastname: Ronning
authors.forename: M
authors.initials: M
authors.lastname: Sutherland
authors.forename: Louis
authors.initials: L
authors.lastname: Taillefer
authors.forename: C
authors.initials: C
authors.lastname: Petrovic
authors.forename: P C
authors.initials: PC
authors.lastname: Canfield
authors.forename: Z
authors.initials: Z
authors.lastname: Fisk