Dependence of proximity-induced supercurrent on junction length in multilayer-graphene Josephson junctions

We report experimental observation of the proximity-induced supercurrent in superconductor-multilayer graphene-superconductor junctions. We find that the supercurrent is a linearly decreasing function of the junction length (separation of the superconducting electrodes), which is quite different from the usual behavior of exponential dependence. We suggest that this behavior originates from the intrinsic large contact resistance between the multilayer and the superconducting electrodes. (C) 2010 Elsevier B.V. All rights reserved.