ISSN:
1077-3118
Source:
AIP Digital Archive
Topics:
Physics
Notes:
High quality Nb/Al-based tunnel junctions, fabricated with a superconducting interface onto thick single crystal x-ray absorbers of Nb and Ta are discussed. Current-voltage characteristics, recorded at 0.5 K, show a subgap current which is still dominated by thermally excited quasiparticles. The quality parameter Rsubgap/Rnormal reaches a value of several million, which is unequalled for nonepitaxially sputtered tunnel junctions. The fabrication process and some development steps, such as preparation of ultrasmooth crystal surfaces are described. Observations of x-ray photons absorbed in Nb and Ta single crystals detected by the superconducting tunnel junctions are also presented. © 1997 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.119865
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