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arXiv · 0810.1730

Fractional Order Shapiro Steps in Superconducting Nanowires

Robert C. Dinsmore III·Myung-Ho Bae·Alexey Bezryadin
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Abstract

We expose superconducting nanowires to microwave radiation in order to study phase lock-in effects in quasi one dimensional superconductors. For sufficiently high microwave powers a resistive branch with Shapiro steps appears in the voltage-current characteristics. At frequencies in the range of 0.9-4 GHz these steps are of integer order only. At higher frequencies steps of 1/2, 1/3, 1/4 and even 1/6 order appear. We numerically model this behavior using a multi-valued current-phase relationship (CPR) for nanowires.

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Robert C. Dinsmore III, Myung-Ho Bae, Alexey Bezryadin. 2008-10-09. Fractional Order Shapiro Steps in Superconducting Nanowires. https://doi.org/10.1063/1.3012360

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