SIS mixers for low noise millimetre-wave heterodyne receivers

Steven R. Davies, C. T. Cunningham, Leslie T. Little

Published Mar 22, 1988• 0 citations

Abstract

The development of ultra-low-noise receivers at frequencies of >200 GHz is primarily driven by astronomical applications. The most sensitive millimeter-wave receivers that have presently been constructed make use of the strong mixing afforded by superconductor-insulator-superconductor (SIS) tunnel junctions. In a collaborative project between UKC and RAL, a 230 GHz laboratory receiver has been built using a lead alloy SIS junction as the mixing element, mounted in 4:1 reduced-height waveguide, terminated at one end with a circular cross-section, adjustable backshort. Best results indicate a double-sideband receiver noise temperature of T/sub R/(DSB) approximately=120 K, which represents state-of-the-art performance at this frequency. Initial difficulties in achieving good mixing performance prompted an investigation into the importance of the 'quality' of mixer block backshort tuning elements. An analysis of the mixer equivalent circuit is presented which allows for loss in a non-ideal mixer block, and 3-port mixer model calculations are discussed which incorporate this analysis into the Tucker quantum theory of mixing.

Related papers

Low-noise SIS heterodyne receiver at 230 GHz

Steven R. Davies, Leslie T. Little, C. T. Cunningham

A 230 GHz laboratory receiver has been built using a superconductor-insulator-superconductor (SIS) junction as the mixing element. The junction is mounted in 4:1 reduced-height waveguide, terminated at one end with a circular adjustable backshort. Recent results indicate a receiver noise temperature of TR ≃ 120 K (DSB).

Electronics LettersAug 27, 19874 citations

Low noise SIS receiver performance using Pb alloy tunnel junctions

Steven R. Davies, Leslie T. Little

A receiver noise temperature of 61 K (DSB) has been measured for a superconductor–insulator–superconductor (SIS) heterodyne receiver operating at 232 GHz, the lowest value reported to date for such a receiver employing a lead alloy junction. Analysis of the losses of the receiver components yields mixer noise temperature and conversion loss, Tm = 24 K and Lm = 2.1 dB (DSB). These are compared with predictions based on 3-port quantum mixer theory, made using the measured characteristics of the junction and an equivalent circuit for the waveguide mixer mount deduced from scaled modelling experiments.

IEE Proceedings - Microwaves Antennas and PropagationJan 1, 19980 citations

Performance of a two-junction array SIS-mixer operating around 345 GHz

Cornelia E. Honingh, Gert J. de Lange, M. M. T. M. Dierichs +3 more

The authors have made a detailed study of the gain and noise of a SIS (superconductor-insulator-superconductor) heterodyne receiver at 345 GHz. An array of two Nb-Al/sub 2/O/sub 3/-Nb SIS junctions in series are used as the mixing element. The array is operated in a waveguide mount with a backshort and an E-plane tuner. The best receiver noise temperature achieved is 140 K DSB (double sideband). The embedding impedances were determined by fitting theory to the measured pumped curves. High-quality fits were obtained, providing the first detailed test of the Tucker-theory at frequencies above 300 GHz. The impedances found by this method are in very good agreement with impedances measured in a scale model at 3.3 GHz. From these embedding impedances, the gain and noise of the mixer were calculated over a full bias range using the Tucker theory in the three-port low-IF approximation. The measured dependence of mixer gain and noise on bias voltage, pump power and embedding impedance is in good agreement with theory. However the absolute values show discrepancies that appear to be independent of the bias parameters of the mixer.>

IEEE Transactions on Microwave Theory and TechniquesApr 1, 199314 citations

Low-noise THz-range Nb based SIS Receivers for Radio Astronomy

Kirill I. Rudakov, Andrey V. Khudchenko, Lyudmila V. Filippenko +4 more

This repost describes our results on development of low-noise heterodyne THz receivers for ground based and space radio astronomy. Superconductor-insulator-superconductor (SIS) mixers that employ high quality Nb-based tunnel junctions are the key element of the most sensitive heterodyne THz receivers. In particular we present here the SIS receivers for frequency range 211-275 GHz and 800-950 GHz with double sideband (DSB) noise temperature of about 25 K and 220 K, respectively. The latest results on development, fabrication techniques and experimental study of the SIS receivers will be discussed.

International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz)Nov 8, 20207 citations

Performance of an SIS receiver over 460 GHz to 640 GHz using submicron Nb junctions with integrated RF tuning circuits

Pascal Febvre

The most sensitive heterodyne receivers used formillimeter wave and submillimeter wave radioastronomyemploy superconductor-insulator-superconductor (SIS)tunnel junctions as the nonlinear mixing element. Goodperformance has recently been reported for SIS junctionsused in planar mixer circuits and waveguide mixers fromabout 300 GHz to 500 GHz. We have developed asubmillimeter wave SIS heterodyne receiver for observingimportant rotational transitions of molecules in theinterstellar medium near 550 GHz and 630 GHz. Thisreceiver is based on a waveguide mixer with an adjustablebackshort and E-plane tuner [1]. The mixer uses a highcurrent density, 0.25 gm2 Nb-A1Ox-Nb tunnel junctiondefined by electron beam lithography [2]. The capacitanceof the junction is compensated with an integrated RFsuperconductive microstrip tuning circuit. The receiverperformance has been measured over the frequency range460 GHz to 640 GHz. DSB receiver noise temperatures aslow as 200 ± 17 K at 540 GHz and 362 ± 33 K at626 GHz have been obtained. In addition, negativedifferential resistance has been observed in the DC I-Vcurve at frequencies around 491 GHz. These results indicatethat the superconductive Nb microstrip transmission linesused in the tuning circuits are low-loss and perform well upto at least 90% of the superconductor energy gap frequency.

International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz)Aug 30, 19930 citations

THz Range Low-Noise SIS Receivers for Space and Ground-Based Radio Astronomy

Kirill I. Rudakov, Andrey V. Khudchenko, Lyudmila V. Filippenko +5 more

We report on research in the field of low-noise receiving systems in the sub-terahertz (THz) range, carried out in recent years, aimed at developing receivers with quantum sensitivity for implementation in space and ground-based radio telescopes. Superconductor-Insulator-Superconductor (SIS) mixers based on high-quality tunnel junctions are the key elements of the most sensitive sub-THz heterodyne receivers. Motivations and physical background for technology improvement and optimization, as well as fabrication details, are described. This article presents the results of the SIS receiver developments for the 211–275 GHz and 790–950 GHz frequency ranges with a noise temperature in the double sideband (DSB) mode of approximTELY 20 K and 200 K, respectively. These designs and achievements are implemented in the development of the receiving systems for the Russian Space Agency mission “Millimetron”, and for the ground-based APEX (Atacama Pathfinder EXperiment) telescope.

Applied SciencesOct 28, 202136 citations