Absolute frequency measurements of the 532 nm radiation recommended for the realization of the metre
Absolute frequency measurement at the International Bureau of Weights and Measures of an iodine-stabilized Nd:YAG laser with λ ≈ 532 nm is reported. The reference laser system Nd:YAG-C stabilized to the a10 component in the R(56) 32-0 line was measured using an optical femtosecond comb set-up. The frequency found was 563 260 223 510.4 kHz with a standard uncertainty of uc = 0.2 kHz. A simplified scheme was used in which the absolute frequency measurements were made possible while controlling only the repetition rate of the comb; this reduces the control of the frequency comb to a one-dimensional problem.
Published in 2003.