Josephson-based full digital bridge for high-accuracy impedance comparisons

This paper describes a Josephson-based impedance bridge capable of comparing any types of impedance over a large bandwidth. The heart of the bridge is a dual AC Josephson Voltage Standard (ACJVS) source which offers unprecedented flexibility in high-precision impedance calibration (i.e., calibration at arbitrary ratios and phase angles) allowing full coverage of the complex plane using a single bridge.