Direct visualization of superconducting vortex lattices under a constant current flow

Abstract

We have developed a method to make scanning tunneling microscopy/spectroscopy imaging at very low temperatures while driving a constant electric current up to some tens of mA through the sample. It gives a new local probe, which we term current driven scanning tunneling microscopy/spectroscopy (CDSTM/S) [1]. Applications include local vortex motion experiments and local density of states studies. In this poster, the possibilities of this technique will be introduced by showing CDSTM/S studies in NbSe2 and W-based amorphous superconducting thin films. Both are the prototype systems to study the electronic structure of superconducting vortex cores and the dynamics of a two dimensional superconducting vortex lattice, respectively. Perspectives of applications will be also presented.