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arXiv · 1206.0193

Single Cooper-pair pumping in the adiabatic limit and beyond

S. Gasparinetti·P. Solinas·Y. Yoon·J. P. Pekola
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Abstract

We demonstrate controlled pumping of Cooper pairs down to the level of a single pair per cycle, using an rf-driven Cooper-pair sluice. We also investigate the breakdown of the adiabatic dynamics in two different ways. By transferring many Cooper pairs at a time, we observe a crossover between pure Cooper-pair and mixed Cooper-pair-quasiparticle transport. By tuning the Josephson coupling that governs Cooper-pair tunneling, we characterize Landau-Zener transitions in our device. Our data are quantitatively accounted for by a simple model including decoherence effects.

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S. Gasparinetti, P. Solinas, Y. Yoon, J. P. Pekola. 2012-06-01. Single Cooper-pair pumping in the adiabatic limit and beyond. https://doi.org/10.1103/physrevb.86.060502

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