Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physica B+C

Negative resistance and conversion gain in SIS mixers

A. D. Smith, William R. McGrath, P. L. Richards, Herman van Kempen, D. E. Prober, Padmanabhan Santhanam

Published Aug 1, 1981• 9 citations
Publisher
DOI
10.1016/0378-4363(81)90982-7

Related papers

Large conversion efficiency and dynamic range for sis mixers

T. C. L. G. Sollner

Physica B+C•Aug 1, 1981•5 citations

Large gain, negative resistance, and oscillations in superconducting quasiparticle heterodyne mixers

William R. McGrath, P. L. Richards, A. D. Smith +2 more

We have measured the properties of a superconductor-insulator-superconductor (SIS) quasiparticle mixer which is operated in the quantum limit. Single sideband conversion gain larger than +4 dB was observed at 36 GHz with a mixer noise temperature T=9 + or - 6K, which is to be compared with the (Planck) quantum limit h-bar omega/(kln2) approx. 2.5K. Complete 3-port mixer calculations are presented which are in good agreement with the gain measurements. Negative resistance was observed which implies that arbitrarily large gain is available.

STIN•Jan 1, 1981•0 citations

Infinite gain and oscillations in SIS microwave mixers

Aldert van der Ziel

Physica B+C•Jun 1, 1983•0 citations

An 85–115 GHz SIS Mixer Demonstrating Nearly Constant Dynamic Resistance

Wenlei Shan, Zhenqiang Li, Jiaqiang Zhong +1 more

We report the design and experiment results of 85-115 GHz SIS mixers that demonstrate nearly constant dynamic resistance and uniform conversion gain. The dynamic resistance close to 50 Omega allows stable bias and direct connection of the SIS mixer and the cryogenic low noise amplifier without an IF isolator. The tuning circuit consists of a single junction tuned by an equivalent shunt inductance and an impedance transformer used for impedance matching. Since the impedance transformer and the shunt inductance have opposite frequency-dependent admittances, we were able to eliminate the frequency-dependent components of the tuning circuit and managed to achieve nearly constant embedding impedance in the frequency range. Measurement results showing dynamic resistances ranging from 30 Omega to 50 Omega and conversion gain changing less than 3 dB reasonably agree with the simulations.

IEEE Transactions on Applied Superconductivity•May 27, 2009•8 citations

A 100 GHz SIS Quasiparticle Mixer with 10 dB Coupled Gain

Antti V. Räisänen, Denis Crété, P. L. Richards +1 more

We have tested a superconducting qussiparticle mixer for 85-110 GHz which gives much larger coupled gain than has been previously observed. When operated with a negative dynamic resistance of about 2000 Omega, the maximum coupled gain was G/sub M/(DSB)= 12.5 +- 0.5 dB [G/sub M/(SSB)= 9.5 +- 2.5 dB]. The associated mixer noise temperature was 15.9 K (DSB). Large gain was also observed with large positive dynamic resistance, giving the lowest mixer noise temperature of 12.4 K (DSB).

IEEE MTT-S International Microwave Symposium digest•Jan 1, 1987•17 citations

Some recent developments in the design of SIS mixers

Anthony R. Kerr, S.-K. Pan

International Journal of Infrared and Millimeter Waves•Oct 1, 1990•90 citations
We have measured the properties of a superconductor-insulator-superconductor (SIS) quasiparticle mixer which is operated in the quantum limit. Single sideband conversion gain larger than +4 dB was observed at 36 GHz with a mixer noise temperature T=9 + or - 6K, which is to be compared with the (Planck) quantum limit h-bar omega/(kln2) approx. 2.5K. Complete 3-port mixer calculations are presented which are in good agreement with the gain measurements. Negative resistance was observed which implies that arbitrarily large gain is available.
We report the design and experiment results of 85-115 GHz SIS mixers that demonstrate nearly constant dynamic resistance and uniform conversion gain. The dynamic resistance close to 50 Omega allows stable bias and direct connection of the SIS mixer and the cryogenic low noise amplifier without an IF isolator. The tuning circuit consists of a single junction tuned by an equivalent shunt inductance and an impedance transformer used for impedance matching. Since the impedance transformer and the shunt inductance have opposite frequency-dependent admittances, we were able to eliminate the frequency-dependent components of the tuning circuit and managed to achieve nearly constant embedding impedance in the frequency range. Measurement results showing dynamic resistances ranging from 30 Omega to 50 Omega and conversion gain changing less than 3 dB reasonably agree with the simulations.