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DOE OSTI · 22280622

Balanced double-loop mesoscopic interferometer based on Josephson proximity nanojunctions

Ronzani, Alberto·Altimiras, Carles·Giazotto, Francesco
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Abstract

We report on the fabrication and characterization of a two-terminal mesoscopic interferometer based on three V/Cu/V Josephson junctions having nanoscale cross-section. The junctions have been arranged in a double-ring geometry realized by metallic thin film deposition through a suspended mask defined by electron beam lithography. Although a significant amount of asymmetry between the critical current of each junction is observed, we show that the interferometer is able to suppress the supercurrent to a level lower than 6 parts per thousand, being here limited by measurement resolution. The present nano-device is suitable for low-temperature magnetometric and gradiometric measurements over the micrometric scale.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYCOPPERCRITICAL CURRENTDEPOSITIONELECTRON BEAMSFABRICATIONINTERFACESINTERFEROMETERSJOSEPHSON JUNCTIONSMASKINGNANOSTRUCTURESTHIN FILMSVANADIUM

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Ronzani, Alberto, Altimiras, Carles, Giazotto, Francesco. 2014-01-20. Balanced double-loop mesoscopic interferometer based on Josephson proximity nanojunctions. https://doi.org/10.1063/1.4862477

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