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Physical Review Letters

Decay of the Zero-Voltage State in Small-Area, High-Current-Density Josephson Junctions

L. D. Jackel, J. P. Gordon, Evelyn L. Hu, Richard E. Howard, Linus A. Fetter, D. M. Tennant, R. W. Epworth, J. Kurkijärvi

Published Aug 31, 1981• 167 citations
Publisher

Abstract

We have measured the distribution in current for the onset of voltage in small-area Josephson junctions for temperatures down to \ensuremath{\sim}1.6 K. The lifetime of the $〈V〉=0$ state for our highest current density junctions becomes temperature independent for ${k}_{\mathrm{B}}T\ensuremath{\lesssim}\frac{\ensuremath{\hbar}{\ensuremath{\omega}}_{0}}{20}$, a $T$ much less than the WKB prediction (${\ensuremath{\omega}}_{0}$ is the junction resonant frequency). This is consistent with the Caldeira-Leggett theory, which includes damping effects on the quantum tunneling rate.

DOI
10.1103/physrevlett.47.697

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