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A Two-Way Josephson Voltage Standard Comparison between NIST and NRC



Yi-hua Tang, Barry Wood, Clark Hamilton


A two-way Josephson voltage standard (JVS) direct comparison between the National Institute of Standards and Technology (NIST) and the National Research Council (NRC) has been conducted. The process consists of two comparisons, which means that the NIST JVS provided a voltage at 10 V and was measured against the NRC JVS with NRC's measuring system (hardware and software). The comparison was repeated by using the NIST JVS measuring system to measure a voltage at 10 V provided by the NRC JVS. The results of the two comparisons are in agreement to within 0.7 nV and their mean indicates that the difference between the two JVSs at 10 V is -0.28 nV with a pooled combined uncertainty of 2.07 nV (k = 2) or relative uncertainty of 2.1 parts in 10^10.
IEEE Transactions on Instrumentation and Measurement


Compact Josephson voltage standard, direct comparison, Josephson voltage standard, uncertainty


Tang, Y. , Wood, B. and Hamilton, C. (2008), A Two-Way Josephson Voltage Standard Comparison between NIST and NRC, IEEE Transactions on Instrumentation and Measurement, [online], (Accessed July 22, 2024)


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Created April 1, 2008, Updated February 17, 2017