Multiband superconductivity in NbSe_2 from heat transport

Etienne Boaknin; M. A. Tanatar; Johnpierre Paglione; D. G. Hawthorn; R. W. Hill; F. Ronning; M. Sutherland; Louis Taillefer; J. Sonier; S. M. Hayden; J. W. Brill

doi:10.1016/j.physc.2004.03.055

arXiv · cond-mat/0304499

Multiband superconductivity in NbSe_2 from heat transport

Etienne Boaknin·M. A. Tanatar·Johnpierre Paglione·D. G. Hawthorn·R. W. Hill·F. Ronning·M. Sutherland·Louis Taillefer·J. Sonier·S. M. Hayden·J. W. Brill

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Abstract

The thermal conductivity of the layered s-wave superconductor NbSe_2 was measured down to T_c/100 throughout the vortex state. With increasing field, we identify two regimes: one with localized states at fields very near H_c1 and one with highly delocalized quasiparticle excitations at higher fields. The two associated length scales are most naturally explained as multi-band superconductivity, with distinct small and large superconducting gaps on different sheets of the Fermi surface.

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Etienne Boaknin, M. A. Tanatar, Johnpierre Paglione, D. G. Hawthorn, R. W. Hill, F. Ronning, M. Sutherland, Louis Taillefer, J. Sonier, S. M. Hayden, J. W. Brill. 2003-04-22. Multiband superconductivity in NbSe_2 from heat transport. https://doi.org/10.1016/j.physc.2004.03.055

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