APPARATUS AND METHOD FOR DEMODULATION OF A MODULATED CURL-FREE MAGNETIC VECTOR POTENTIAL FIELD

摘要

A system for determining the modulation imposed on a curl-free magnetic vector potential field. The system includes apparatus for detecting the curlfree magnetic vector potential field component by means of a Josephson junction. The magnetic vector potential field interacts with the Josephson junction by var-ying the phase of the argument of the sine function which determines the Josephson junction current. The output signals of the Josephson junction are coupled to apparatus that can determine the modulation of the detected field. Because the magnitude of the change in the detected curl-free vector potential field causes a proportional change in the phase of the Josephson junction current, the modulation of the field can be established.