Tuning the influence of microscopic decoherence on the superconducting proximity effect in a graphene Andreev interferometer.
نویسندگان
چکیده
We discuss transport measurements through graphene Andreev interferometers exhibiting reentrance of the superconducting proximity effect. We observe that at high gate voltage (VBG) the energy dependence of the Andreev conductance oscillations exhibits a scaling in agreement with theoretical expectations, which breaks down at low VBG, when the Fermi energy approaches the charge neutrality point. The phenomenon is a manifestation of single particle dephasing that increasingly limits the propagation of superconducting correlations away from the superconductor-graphene interface. Our work addresses the interplay between microscopic decoherence and superconductivity, and shows that graphene provides a useful experimental platform to investigate unexplored regimes and phenomena in the superconducting proximity effect.
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عنوان ژورنال:
- Physical review letters
دوره 112 12 شماره
صفحات -
تاریخ انتشار 2014