Title :
A 200-285-GHz waveguide SIS mixer with an inhomogeneous distributed junction array
Author :
Takeda, Masanori ; Noguchi, Takashi
Author_Institution :
Dept. of Astronomical Sci., Graduate Univ. for Adv. Studies, Nagano, Japan
fDate :
11/1/2002 12:00:00 AM
Abstract :
In this paper, we present the experimental results of a waveguide superconductor-insulator-superconductor (SIS) mixer with an inhomogeneous distributed junction array. The mixer consists of five Nb-AlOx-Nb SIS junctions with different dimensions distributed on a superconducting microstrip. The critical current density of the fabricated junctions was 3100 A/cm2. Detailed measurements of the receiver noise temperature have been made in the frequency range from 190 to 284 GHz at 4.2 K. A double-sideband (DSB) receiver noise temperature of 5 hw/k was obtained in the frequency range from 202 to 284 GHz and the lowest DSB receiver noise temperature of 46 K was obtained at 210 GHz.
Keywords :
aluminium compounds; critical current density (superconductivity); microstrip lines; millimetre wave mixers; millimetre wave receivers; niobium; superconducting arrays; superconducting device noise; superconducting microwave devices; superconductor-insulator-superconductor mixers; 200 to 285 GHz; 4.2 K; Nb-AlO-Nb; corrugated feed horns; critical current density; double-sideband receiver noise temperature; heterodyne receiver; inhomogeneous distributed junction array; microwave computer-aided design; multiple junctions; normal-state resistance; optimized junction array; receiver noise temperature; superconducting microstrip; waveguide superconductor-insulator-superconductor mixer; Bandwidth; Critical current density; Frequency; Josephson junctions; Mixers; Superconducting device noise; Superconducting devices; Superconducting transmission lines; Temperature distribution; Waveguide junctions;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2002.804513
