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Physical Review Letters

Macroscopic Quantum Tunneling in 1-μm Nb Josephson Junctions

Richard F. Voss, R. A. Webb

Published Jul 27, 1981• 435 citations
Publisher

Abstract

The probability distributions for switching out of the superconducting state of low-cur-rent-density 1-\ensuremath{\mu}m Nb Josephson junctions with capacitance \ensuremath{\approx} 0.1 pF have been measured as a function of temperature $T$ down to 3 mK. Below 100 mK the distribution widths become independent of $T$. The results are in excellent agreement with predictions for the quantum tunneling of the (macroscopic) junction phase that include the reduction of tunneling rates due to dissipation.

DOI
10.1103/physrevlett.47.265

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The probability distributions for switching out of the superconducting state of low-cur-rent-density 1-\ensuremath{\mu}m Nb Josephson junctions with capacitance \ensuremath{\approx} 0.1 pF have been measured as a function of temperature TTT down to 3 mK. Below 100 mK the distribution widths become independent of TTT. The results are in excellent agreement with predictions for the quantum tunneling of the (macroscopic) junction phase that include the reduction of tunneling rates due to dissipation.
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