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Subharmonic gap structure in short ballistic graphene junctions

J. C. Cuevas·A. Levy Yeyati
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Abstract

We present a theoretical analysis of the current-voltage characteristics of a ballistic superconductor-normal-superconductor (SNS) junction, in which a strip of graphene is coupled to two superconducting electrodes. We focus in the short-junction regime, where the length of the strip is much smaller than superconducting coherence length. We show that the differential conductance exhibits a very rich subharmonic gap structure which can be modulated by means of a gate voltage. On approaching the Dirac point the conductance normalized by the normal-state conductance is identical to that of a short diffusive SNS junction.

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J. C. Cuevas, A. Levy Yeyati. 2006-09-06. Subharmonic gap structure in short ballistic graphene junctions. https://doi.org/10.1103/physrevb.74.180501

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