Shapiro Steps in the Absence of Microwave Radiation

Lin He; Jian Wang; Moses H. W. Chan

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arXiv · 1107.0061

Shapiro Steps in the Absence of Microwave Radiation

Lin He·Jian Wang·Moses H. W. Chan

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Abstract

The current-voltage I-V characteristics of a 1.2 \mum long Au nanowire contacted by superconducting electrodes were studied in details. Interestingly, the I-V curves over a wide range of temperatures display multiple steps at voltages V = (m/n)(V0/2e) in the absence of microwave radiation, where m, n are integer numbers and V0 ~ 92 \muV. We posit that these steps are the subharmonic Shapiro steps due to the interplay of the ac Josephson current and a minigap in the Au nanowire induced by superconducting electrodes via the proximity effect.

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Lin He, Jian Wang, Moses H. W. Chan. 2011-06-30. Shapiro Steps in the Absence of Microwave Radiation. https://arxiv.org/abs/1107.0061

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