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arXiv · 1412.8451

Cooper Pair Splitting by means of Graphene Quantum Dots

Z. B. Tan·D. Cox·T. Nieminen·P. Lähteenmäki·D. Golubev·G. B. Lesovik·P. J. Hakonen
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Abstract

Split Cooper pair is a natural source for entangled electrons which is a basic ingredient for quantum information in solid state. We report an experiment on a superconductor-graphene double quantum dot (QD) system, in which we observe Cooper pair splitting (CPS) up to a CPS efficiency of ~ 10%. With bias on both QDs, we are able to detect a positive conductance correlation across the two distinctly decoupled QDs. Furthermore, with bias only on one QD, CPS and elastic co-tunneling can be distinguished by tuning the energy levels of the QDs to be asymmetric or symmetric with respect to the Fermi level in the superconductor.

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Z. B. Tan, D. Cox, T. Nieminen, P. Lähteenmäki, D. Golubev, G. B. Lesovik, P. J. Hakonen. 2014-12-29. Cooper Pair Splitting by means of Graphene Quantum Dots. https://doi.org/10.1103/physrevlett.114.096602

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