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Applied Physics Letters

Signal and white noise properties of edge junction dc SQUID’s

Ronald T. Wakai, Dale J. Van Harlingen

Published Apr 4, 1988• 21 citations
Publisher

Abstract

We have fabricated and characterized the noise performance of submicron edge junction dc superconducting quantum interference devices (SQUID’s) which exhibit excellent signal properties and extremely high flux sensitivity. At frequencies above about 3 MHz, the SQUID noise is white and is in reasonable agreement with computer simulations for a thermal noise-limited detector. In one device the measured flux energy resolution is 1.6±0.5ℏ at 1.5 K, within a factor of 2 of the quantum-limited value suggested by theoretical modeling.

DOI
10.1063/1.99197

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