High quality superconducting tunnel junctions on Nb and Ta single crystals for radiation detection

Journal Article · Mon Sep 01 04:00:00 EDT 1997 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.119865· OSTI ID:538386

Bruijn, M P; Kiewiet, F B; van den Berg, M L; Luiten, O J; de Korte, P A ^[1]; Hamster, A W; Brons, C G; Flokstra, J ^[2]

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1. Space Research Organization Netherlands, 3584 CA Utrecht (The Netherlands)
2. University of Twente, Faculty of Applied Physics, 7500 AE Enschede (The Netherlands)

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 R{sub subgap}/R{sub normal} 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. {copyright} {ital 1997 American Institute of Physics.}

• OSTI ID: 538386
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 9 Vol. 71; ISSN 0003-6951; ISSN APPLAB
• Country of Publication: United States
• Language: English

Related Subjects

44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
66 PHYSICS
MONOCRYSTALS
NIOBIUM
RADIATION DETECTION
SUPERCONDUCTING JUNCTIONS
TANTALUM
TUNNEL EFFECT
X RADIATION
X-RAY DETECTION