1.   µ-wave induced constant voltage current-steps

2.   predicted in 1962 in superconductors

3.   measured in 1967 at 21 ppm: Parker

4.   2eV_n = nhv gives e/h

5.   Also requires calculatable capacitor and chain of resistance calibration.

6.   used for 1986 CODATA at 45 ppb

7.   Gave value of 137.035 9871(43) at 32 ppb

prev toc tos next