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Fluctuation Dominated Josephson Tunneling with a Scanning Tunneling Microscope

O. Naaman·W. Teizer·R. C. Dynes
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Abstract

We demonstrate Josephson tunneling in vacuum tunnel junctions formed between a superconducting scanning tunneling microscope tip and a Pb film, for junction resistances in the range 50-300 k$Ω$. We show that the superconducting phase dynamics is dominated by thermal fluctuations, and that the Josephson current appears as a peak centered at small finite voltages. In the presence of microwave fields (f=15.0 GHz) the peak decreases in magnitude and shifts to higher voltages with increasing rf power, in agreement with theory.

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O. Naaman, W. Teizer, R. C. Dynes. 2001-03-10. Fluctuation Dominated Josephson Tunneling with a Scanning Tunneling Microscope. https://doi.org/10.1103/physrevlett.87.097004

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