Development of 10-Vrms sampling measurement system using AC-programmable Josephson voltage standard

Abstract

We are developing a 10-Vrms low-frequency sampling measurement system using an AC-programmable Josephson voltage standard (AC-PJVS). Our AC-PJVS circuit is composed of NbN-based over-damped Josephson junctions cooled with a compact cooler. A PJVS chip with 524,288 junctions increases the maximum measurable root-mean-square (rms) voltage up to 10 V at a microwave bias of 15.9 GHz. We have obtained a differential waveform between the stepwise-approximated waveforms of the AC-PJVS and the sinusoidal waveforms of a calibrator.