Applied Physics Letters

Low-noise tunnel junction dc SQUID’s

Michael W. Cromar, P. Carelli

Published May 1, 1981• 87 citations

Abstract

We present the results of an investigation of thin-film dc super conducting quantum interference device (SQUID’s) with very high energy resolution. The SQUID’s were fabricated using integrated-circuit techniques appropriate for superconducting devices. A weakly coupled SQUID with very low inductance (1 pH) had an intrinsic energy sensitivity 6×10−34 J/Hz = 0.9 h. A well-coupled SQUID (coupling constant α = 0.43) had an energy sensitivity referred to the input coil of 4.7×10−32 J/Hz = 71 h.

DOI: 10.1063/1.92472

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