Josephson effect in small - area superconducting tunnel junctions at 604
نویسنده
چکیده
We have measured the ac Josephson effect in small-area superconducting tunnel junctions at 604 GHz (A = 496pm) using a resonant planar dipole antenna to couple the radiation into the junction. In a 176-fl junction, we have observed up to the 7th Josephson step (at 8.75 m V), a performance comparable to that seen in point contacts. We also compare our data with the results of the RSJ model and of the Werthamer theory.
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