Onset of Quantized Thermal Fluctuations in "One-Dimensional" Superconductors

Abstract

Measurements of the onset of the resistive transition and the current-voltage characteristics of "one-dimensional" single-crystal tin whiskers have been extended to a sensitivity of ${10}^{\ensuremath{-}15}$ V. The thermally activated quantum phase slips proposed by Langer and Ambegaokar have been observed directly and their theory for the voltage, determined by the rate of phase slippage, has been verified together with the modification of the attempt frequency proposed by McCumber and Halperin.