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arXiv · 1209.3626

Coherent Cooper-pair pumping by magnetic flux control

S. Gasparinetti·I. Kamleitner
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Abstract

We introduce and discuss a scheme for Cooper-pair pumping. The scheme relies on the coherent transfer of a superposition of charge states across a superconducting island and is realized by adiabatic manipulation of magnetic fluxes. Differently from previous implementations, it does not require any modulation of electrostatic potentials. We find a peculiar dependence of the pumped charge on the superconducting phase bias across the pump and that an arbitrarily large amount of charge can be pumped in a single cycle when the phase bias is π. We explain these features and their relation to the adiabatic theorem.

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S. Gasparinetti, I. Kamleitner. 2012-12-17. Coherent Cooper-pair pumping by magnetic flux control. https://doi.org/10.1103/physrevb.86.224510

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