All refractory light-sensitive superconductive junctions

A procedure for fabricating all refractory superconducting tunnel junctions with a semiconducting barrier has been developed. The process is based on the deposition of a four-layer Nb-Al-CdS-Nb structure without breaking the vacuum. The photoconducting properties of the barrier produce a light-sensitive behavior of the junctions. Preliminary measurements have shown the occurrence of light induced quasiparticle tunneling. © 1996 American Institute of Physics.