Intrinsic Superconductivity in Ropes of Carbon Nanotubes

Abstract

We have developed a technique for measuring transport measurements on carbon nanotubes at very low temperature. Carbon nanotubes are connected through low contact resistance to metallic pads. It has been possible to observe intrinsic superconductivity in ropes of single wall carbon nanotubes mounted on normal contacts provided that the distance between the normal electrodes is large enough, otherwise superconductivity is destroyed by proximity effect. These experiments indicate the presence of attractive interactions in carbon nanotubes which overcome coulomb repulsive interactions at low temperature.