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Superconducting nanobridges under magnetic fields

J. G. Rodrigo·H. Suderow·S. Vieira
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Abstract

We report on the study of superconducting nanotips and nanobridges of lead with a Scanning Tunnelling Microscope in tunnel and point contact regimes. We deal with three different structures. A nanotip that remains superconducting under a field of 2 T. For this case we present model calculations of the order parameter, which are in good agreement with the experiments. An asymmetric nanobridge of lead showing a two steps loss of the Andreev excess current due to different heating and dissipation phenomena in each side of the structure. A study of the effect of the thermal fluctuations on the Josephson coupling between the two sides of a superconducting nanobridge submitted to magnetic fields. The different experiments were made under magnetic fields up to twenty five times the volume critical field of lead, and in a temperature range between 0.6 K and 7.2 K.

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J. G. Rodrigo, H. Suderow, S. Vieira. 2003-04-24. Superconducting nanobridges under magnetic fields. https://doi.org/10.1002/pssb.200301798

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