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Effect of thermal phase fluctuations on the superfluid density of two-dimensional superconducting films

Stefan J. Turneaure·Thomas R. Lemberger·John M. Graybeal
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Abstract

High precision measurements of the complex sheet conductivity of superconducting Mo77Ge23 thin films have been made from 0.4 K through Tc. A sharp drop in the inverse sheet inductance, 1/L(T), is observed at a temperature, Tc, which lies below the mean-field transition temperature, Tco. Just below Tc, the suppression of 1/L(T) below its mean-field value indicates that longitudinal phase fluctuations have nearly their full classical amplitude, but they disappear rapidly as T decreases. We argue that there is a quantum crossover at about 0.94 Tco, below which classical phase fluctuations are suppressed.

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Stefan J. Turneaure, Thomas R. Lemberger, John M. Graybeal. 1999-07-02. Effect of thermal phase fluctuations on the superfluid density of two-dimensional superconducting films. https://doi.org/10.1103/physrevlett.84.987

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