1.
Opt Lett
; 20(10): 1095-7, 1995 May 15.
Artigo
em Inglês
| MEDLINE
| ID: mdl-19859436
RESUMO
We have checked whether the frequency ratio between fundamental and second-harmonic optical frequencies is exactly 1:2 by measuring the frequency difference between the second harmonics of two diode lasers and comparing it with the frequency difference of the fundamentals. We have improved the 30-year-old experimental limit on the accuracy of the 1:2 frequency ratio by 7 orders of magnitude for frequency-dependent shifts to 2.3 parts in 10(13) for a KNbO(3) crystal.