Supercurrent on a vortex core in 2H-NbSe2: Current-driven scanning tunneling spectroscopy measurements

We report current-driven scanning tunneling spectroscopy (CDSTS) measurements at very low temperatures on vortices in 2H-NbSe2.We find that a current produces an increase of the density of states at the Fermi level in between vortices and a reduction of the zero-bias peak at the vortex center. This occurs well below the depairing current. We conclude that a supercurrent affects the low-energy part of the superconducting gap structure of 2H-NbSe2P. Rodiere provided us with the 2H-NbSe2 sample.We acknowledge support from MINECO and MEC of Spain (the Consolider Ingenio Molecular Nanoscience CSD2007-00010 program, FIS2011-23488, ACI-2009-0905, and an FPU grant), of COST MP1201, and of the Comunidad de Madrid through the Nanobiomagnet progra