NBS Determination of the Fine-Structure Constant, and of the Quantized Hall Resistance and Josephson Frequency to Voltage Quotient in Si Units

Abstract

Results from NBS experiments to realize the ohm and the watt, to determine the proton gyromagnetic ratio and the time dependence of the NBS ohm using the quantum Hall effect, and to maintain the NBS volt using the Josephson effect, are appropriately combined to obtain a highly accurate value of the fine-structure constant and of the quantized Hall resistance in SI units, and accurate values in SI units of the Josephson frequency to voltage quotient, Planck constant, and elementary charge.