Unpaired Electrons in the Heavy-Fermion Superconductor CeCoIn_{5}

M. A. Tanatar; Johnpierre Paglione; S. Nakatsuji; D. G. Hawthorn; E. Boaknin; R. W. Hill; F. Ronning; M. Sutherland; Louis Taillefer; C. Petrovic; P. C. Canfield; Z. Fisk

doi:10.1103/physrevlett.95.067002

arXiv · cond-mat/0503342

Unpaired Electrons in the Heavy-Fermion Superconductor CeCoIn_{5}

M. A. Tanatar·Johnpierre Paglione·S. Nakatsuji·D. G. Hawthorn·E. Boaknin·R. W. Hill·F. Ronning·M. Sutherland·Louis Taillefer·C. Petrovic·P. C. Canfield·Z. Fisk

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Abstract

Thermal conductivity and specific heat were measured in the superconducting state of the heavy fermion material Ce_{1-x}La_{x}CoIn_{5}. With increasing impurity concentration x, the suppression of T_{c} is accompanied by the increase in the 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.

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M. A. Tanatar, Johnpierre Paglione, S. Nakatsuji, D. G. Hawthorn, E. Boaknin, R. W. Hill, F. Ronning, M. Sutherland, Louis Taillefer, C. Petrovic, P. C. Canfield, Z. Fisk. 2005-08-10. Unpaired Electrons in the Heavy-Fermion Superconductor CeCoIn_{5}. https://doi.org/10.1103/physrevlett.95.067002

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