Input noise in the hysteretic rf SQUID: Theory and experiment

Journal Article · Sat Mar 01 04:00:00 EST 1980 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.327782· OSTI ID:5541373

Hollenhorst, J N; Giffard, R P

The spectral density of the low-frequency open-circuit intrinsic input noise of the hysteretic rf-biased SQUID is calculated. The noise level, which affects the optimized power sensitivity of the SQUID, is found to be strongly model dependent and thus also constitutes an interesting probe of device physics. The results of the calculation are significantly different from previous predictions. A direct measurement of the total input noise of a typical rf-biased SQUID system is reported. The results, which are consistent our calculation, correspond to a system noise temperature of 3.1 +- 0.4 mK at a frequency of 1 kHz. This value is consistent with the Manley-Rowe equations and with previous experimentally determined upper limits.

• Research Organization: Department of Physics, Stanford University, Stanford, California 94305
• OSTI ID: 5541373
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 51:3; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

420201* -- Engineering-- Cryogenic Equipment & Devices
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COMPARATIVE EVALUATIONS
DATA
ELECTRONIC EQUIPMENT
FLUXMETERS
HYSTERESIS
INFORMATION
MATHEMATICAL MODELS
MEASURING INSTRUMENTS
MICROWAVE EQUIPMENT
NOISE
SENSITIVITY
SPECTRA
SQUID DEVICES
SUPERCONDUCTING DEVICES