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Applied Physics Letters

Low-frequency noise in low 1/f noise dc SQUID’s

Vittorio Foglietti, W. J. Gallagher, M. B. Ketchen, Alan W. Kleinsasser, R. H. Koch, Stanley I. Raider, Robert L. Sandstrom

Published Nov 17, 1986• 103 citations
Publisher

Abstract

We demonstrate that the low-frequency noise in our edge junction dc superconducting quantum interference devices, with a basic 1/f flux noise of 2×10−12 Φ20/Hz at 1 Hz, can all be accounted for in terms of junction critical current fluctuations. A novel modulation readout scheme is able to cancel the effect of junction critical current fluctuations and reduce our total noise to 1×10−12 Φ20/Hz at 0.1 Hz, a level that is three times lower than the lowest flux noise ever previously reported at this frequency.

DOI
10.1063/1.97334

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