Doping dependence of superconducting gap in YBa_2Cu_3O_y from universal heat transport

Mike Sutherland; D. G. Hawthorn; R. W. Hill; F. Ronning; S. Wakimoto; H. Zhang; C. Proust; E. Boaknin; C. Lupien; M. A. Tanatar; J. Paglione; R. Liang; D. A. Bonn; W. N. Hardy; Louis Taillefer

doi:10.1016/j.physc.2004.03.104

arXiv · cond-mat/0304498

Doping dependence of superconducting gap in YBa_2Cu_3O_y from universal heat transport

Mike Sutherland·D. G. Hawthorn·R. W. Hill·F. Ronning·S. Wakimoto·H. Zhang·C. Proust·E. Boaknin·C. Lupien·M. A. Tanatar·J. Paglione·R. Liang·D. A. Bonn·W. N. Hardy·Louis Taillefer

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Abstract

Thermal transport in the T -> 0 limit was measured as a function of doping in high-quality single crystals of the cuprate superconductor YBa_2Cu_3O_y. The residual linear term kappa_0/T is found to decrease as one moves from the overdoped regime towards the Mott insulator region of the phase diagram. The doping dependence of the low-energy quasiparticle gap extracted from kappa_0/T is seen to scale closely with that of the pseudogap, arguing against a non-superconducting origin for the pseudogap. The presence of a linear term for all dopings is evidence against the existence of a quantum phase transition to an order parameter with a complex (ix) component.

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Mike Sutherland, D. G. Hawthorn, R. W. Hill, F. Ronning, S. Wakimoto, H. Zhang, C. Proust, E. Boaknin, C. Lupien, M. A. Tanatar, J. Paglione, R. Liang, D. A. Bonn, W. N. Hardy, Louis Taillefer. 2003-04-22. Doping dependence of superconducting gap in YBa_2Cu_3O_y from universal heat transport. https://doi.org/10.1016/j.physc.2004.03.104

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