The Chinese 2e/h precision determination: China establishes its National Josephson Voltage Standard

A measuring system for the precise determination 2e/h has been established recently and the National Voltage Standard using Josephson effect has been legally adopted in China. The total uncertainty of the measurement system is 3 × 10⁻⁸ with an accuracy of 1.1 × 10⁻⁷ for the value of 2e/h. The final experimental result is 2e/h = (483 593.846 ± 0.053) GHz/V83-NIM, referred to the volt as maintained by the National Institute of Metrology (NIM), Dayi County, Sichuan, China after January 1, 1983.