Title :
SNAP structures with Nb-AlOx-Nb junctions for MM-wave receivers
Author :
Ermakov, An.B. ; Koshelets, V.P. ; Serpuchenko, I.L. ; Filippenko, L.V. ; Shitov, S.V. ; Vystavkin, A.N.
Author_Institution :
Inst. of Radio Eng. & Electron., Acad. of Sci., Moscow, USSR
fDate :
3/1/1989 12:00:00 AM
Abstract :
High-quality small-area Nb-AlOx-Nb junctions have been fabricated by the selective niobium anodization process (SNAP). The influence of the preparation conditions on the junction properties were investigated. Numerical calculations based on I-V (current-voltage) characteristics measured by a data acquisition system were used to simulate the mixer performance. It has been shown that the knee-shaped structure on the I-V curve of refractory material junctions significantly affects the signal properties of the mixer. The signal and noise properties for different types of integrated SIS (superconductor-insulator-superconductor) mixing elements have been investigated experimentally in the frequency range of 37-53 GHz; the mixer conversion loss was as low as 4 dB at 45 GHz. The mixing elements consist of an odd number of SIS junctions connected in series for RF and in parallel for DC biasing. The DC bias wiring and IF (intermediate frequency) filters of these structures were designed to provide tuning out of junction capacitance and thin-film-electrode inductance
Keywords :
aluminium compounds; anodisation; electron device noise; mixers (circuits); niobium compounds; receivers; solid-state microwave circuits; solid-state microwave devices; superconducting junction devices; type II superconductors; 37 to 53 GHz; 4 dB; DC bias wiring; EHF; I-V curve; IF filters; MM-wave receivers; Nb-AlOx-Nb junctions; SIS junctions; SNAP structures; conversion loss; current-voltage characteristics; integrated SIS mixing elements; knee-shaped structure; mixer performance; noise properties; preparation conditions; refractory material junctions; selective niobium anodization process; signal properties; superconductor-insulator-superconductor; Current measurement; Data acquisition; Frequency conversion; Josephson junctions; Mixers; Niobium; Radio frequency; Superconducting device noise; Superconducting devices; Superconducting materials;
Journal_Title :
Magnetics, IEEE Transactions on
