Superconducting Fractal Multilayers

Abstract

The influence of fractal geometry on superconductivity has been studied for layered superconductors. Superconducting multilayers consisting of alternating Nb and Cu layers with fractal stacking sequence and fractal dimension Df=0.63 including the two limiting cases Df= 0 (single superconducting film) and Df=1 (periodic multilayers) were prepared by electron-beam evaporation in ultrahigh vacuum.