Supercurrent on a vortex core in 2H-NbSe$_2$: current driven scanning tunneling spectroscopy

TL;DR

This study uses current driven scanning tunneling spectroscopy to investigate how supercurrents influence the electronic structure of vortices in 2H-NbSe2, revealing modifications in the density of states and vortex core features.

Contribution

It demonstrates the impact of supercurrents on vortex core electronic states in 2H-NbSe2 using a novel spectroscopic approach.

Findings

Supercurrent increases the density of states at the Fermi level between vortices.

Supercurrent reduces the zero bias peak at vortex centers.

Effects occur below the de-pairing current.

Abstract

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 de-pairing current. We conclude that a supercurrent affects the low energy part of the superconducting gap structure of 2H-NbSe2.