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Implementation of Programmable Josephson Voltage Standard to NIST Voltage Dissemination System



June E. Sims, Yi-hua D. Tang


For about seventy years, from the establishment in 1901 of the predecessor of NIST, the National Bureau of Standards (NBS), until about 1972, the U.S. legal volt was maintained by several groups of electrochemical cells. Beginning in 1972, NBS relied on the Josephson effect - a quantum phenomenon to maintain the unit of voltage in the U.S. The primary standard cell groups have been still playingcontinued to play a critical role for in disseminating the volt from the NIST Josephson voltage standard to the customer benchcalibration customers. The advantage of using standard cells is their long-term predictability with lower noise compared to other types of voltage standards, such as Zener standards. But, the sStandard cells, however, can be affected by power outage, environmental temperature fluctuation, internal degassing, vibration, etc. Sometimes, the voltage shift that occurs after the disturbance can be permanent. The programmable Josephson voltage standard (PJVS) provides current biased quantized voltage steps without the step jump problem that often occursrred in the non-biased Josephson voltage standard. This unique property makes it possible to use the PJVS as a back-up system and eventually to replacea possible replacement for the primary standards cell groups that are used in the NIST volt dissemination chain. The implementation of the PJVS can shorten the dissemination chain and improve the reliability and efficiency of the dissemination system. This paper describes the working principle of the PJVS and the present implementation status of the PJVS to the NIST voltage dissemination system.
Measure: The Journal of Measurement Science


programmable Josephson junction array, programmable Josephson voltage standard (PJVS), representation of SI volt, SI volt, standard cell, US Legal volt, voltage dissemination chain


Sims, J. and Tang, Y. (2006), Implementation of Programmable Josephson Voltage Standard to NIST Voltage Dissemination System, Measure: The Journal of Measurement Science, [online], (Accessed May 20, 2024)


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Created May 31, 2006, Updated October 12, 2021