STM STUDIES OF THE PROXIMITY EFFECT IN SUPERCONDUCTING WIRES WITH ARTIFICIAL PINNING CENTERS

Scanning tunneling microscopy and spectroscopy were applied to study t he proximity effect with nanometer spatial resolution. The measurement s were conducted on novel superconducting wires, which consist of an o rdered array of submicron diameter normal metal filaments (Cu, Mi) emb edded in a superconducting (NbTi) matrix. Spatially resolved informati on about the local density of states is obtained by taking I-V curves simultaneously with topographic images. Our data provide direct eviden ce on the interplay between the normal and superconducting constituent s in the vicinity of the interface between them.