Quantum limited quasiparticle mixers at 100 GHz

Conference · Fri Mar 01 04:00:00 EST 1991 · IEEE Transactions on Magnetics (Institute of Electrical and Electronics Engineers); (United States)

OSTI ID:6047805

Mears, C A; Hu, Q; Richards, D L ^[1]; Worsham, A A; Prober, D E ^[2]; Raisanen, A V ^[3]

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1. Lawrence Berkeley Lab., CA (United States)
2. Yale Univ., New Haven, CT (United States). Dept. of Applied Physics
3. Helsinki Univ. of Technology, Espoo (Finland). Radio Lab.

This paper reports on accurate measurements of the noise and gain of superconducting-insulating-superconducting (SIS) mixers employing small area (1 {mu}m{sup 2}) Ta/Ta{sub 2}O{sub 5}/Pb{sub 0.9}Bi{sub 0.1} tunnel junctions. The authors measured an added mixer noise of 0.61 {plus minus} 0.31 quanta at 95.0 GHz, which is within 25 percent of the quantum limit of 0.5 quanta. The authors carried out a detailed comparison between theoretical predictions of the quantum theory of mixing and experimentally measured noise and gain. The authors used the shapes of I-V curves pumped at the upper and lower sideband frequencies to deduce values of the embedding admittances of these frequencies. Using these admittances, the mixer noise and gain predicted by quantum theory are in excellent agreement with experiment.

• OSTI ID: 6047805
• Report Number(s): CONF-900944--
• Conference Information: Journal Name: IEEE Transactions on Magnetics (Institute of Electrical and Electronics Engineers); (United States) Journal Volume: 27:2
• Country of Publication: United States
• Language: English

Related Subjects

661100 -- Classical & Quantum Mechanics-- (1992-)
665411* -- Basic Superconductivity Studies-- (1992-)
665412 -- Superconducting Devices-- (1992-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMPLIFICATION
BISMUTH COMPOUNDS
BISMUTH OXIDES
CALCULATION METHODS
CHALCOGENIDES
DISPERSIONS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
GAIN
JUNCTIONS
LEAD
MECHANICS
METALS
MIXTURES
NOISE
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
QUANTUM MECHANICS
REFRACTORY METAL COMPOUNDS
SUPERCONDUCTING JUNCTIONS
SUPERCONDUCTIVITY
TANTALUM COMPOUNDS
TANTALUM OXIDES
TRANSITION ELEMENT COMPOUNDS
TUNNEL EFFECT