Some novel superconductor-insulator superlattice systems, Nb0.53Ti0.47Ge, Nb0.53Ti0.47Si and Nb3SnGe were synthesized with the dc sputtering technique. The parallel upper critical fields at zero temperature of these superlattices were estimated to be many times larger than their respective bulk values, due to the quasi-2D nature of the superconducting layers and associated fluxoid accomodation within the insulating layers. The disorder related quantum effects of weak anti-localization, electron interaction and superconducting fluctuations were also observed in these superlattices. The experimental data were compared with recent theories and the analysis provided microscopic information on these quasi-2D superconductors.
ASJC Scopus subject areas