Applied Physics Letters

Measurement of the input impedance of a RF biased SQUID

Franco Bordoni, P. Carelli, I. Modena, Gian Luca Romani

Published Oct 15, 1979• 3 citations

Abstract

An experimental method to measure the imaginary and real part of the input impedance of an rf biased SQUID is described. The experimental results are in good agreement with the predictions of a detailed theoretical model of the rf SQUID, recently published. In particular it seems confirmed that the real part of the input impedance has a negative value which depends on the square of the input signal frequency. This effect must be taken into account whenever a SQUID is used to measure high frequency signals.

DOI: 10.1063/1.91236

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