Cryocooled 10 V Programmable Josephson Voltage Standard at CMS

The cryocooled 10 V Programmable Josephson Voltage Standard (PJVS) system was successfully set up at Center for Measurement Standards (CMS) in Taiwan. In order to more precisely evaluate the performance of this system, we directly compared the cryocooler PJVS system and NIST's portable PJVS system. The comparison result shows excellent agreement between these two systems. The agreement between these two systems at 1.018 V was −0.10 nV with a combined standard uncertainty of 1.04 nV, and −0.07 nV at 10 V with a combined standard uncertainty of 1.22 nV or a relative standard uncertainty of $1.22\times 10^{-10}$ at the 95 % level of confidence.