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Nonequilibrium ac Josephson effect in mesoscopic Nb-InAs-Nb junctions

K. W. Lehnert·N. Argaman·H. -R. Blank·K. C. Wong·S. J. Allen·E. L. Hu·H. Kroemer
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Abstract

Microwave irradiation of Nb-InAs-Nb junctions reveals frequency-doubled Josephson currents which persist to high temperatures, in the absence of a critical current. A nonequilibrium dynamical model, based on time-dependent Andreev bound states, successfully accounts for the resulting half-integer Shapiro step and an enhancement in the conductance near zero bias.

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K. W. Lehnert, N. Argaman, H. -R. Blank, K. C. Wong, S. J. Allen, E. L. Hu, H. Kroemer. 1999-01-03. Nonequilibrium ac Josephson effect in mesoscopic Nb-InAs-Nb junctions. https://doi.org/10.1103/physrevlett.82.1265

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