Cryocooled Josephson standards for AC voltage metrology

P Durandetto, A Sosso, E Monticone, B Trinchera, M Fretto, V Lacquaniti
2017 Journal of Physics, Conference Series  
The Josephson effect is worldwide used as a basis for constant reference voltages in national metrological institutes and in calibration laboratories of industry. Research on Josephson voltage standards is aiming at a fundamental change also in the metrology of the volt for AC and arbitrary waveforms: programmable Josephson voltage standards converting a digital code into a quantum-accurate stepwise waveform are already available in primary laboratories and even more advanced standards for
more » ... rting sub-nanosecond binary coded pulses into any arbitrary signal with quantum accuracy are now actively developed and tested. A new experimental setup based on a two-stage Gifford-McMahon cryocooler has been developed at INRiM for the operation of AC-Josephson voltage standards. Among its distinct features, the possibility of employing both the aforementioned techniques (programmable and pulsed Josephson voltage standards) is particularly interesting. Quantum-based AC voltage sine waves have been synthesized with both programmable and pulse-driven arrays, although their accuracy is still limited by thermal oscillations due to the cryocooler piston motion.
doi:10.1088/1742-6596/841/1/012031 fatcat:ni34hd54dbawfaaow6wzv5eexe