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Optical frequency / wavelentgh references



Leo W. Hollberg, Christopher W. Oates, G Wilpers, C Hoyt, Zeb Barber, Scott A. Diddams, W Oskay, James C. Bergquist


Ideas for using visible light from atomic transitions for precision instrumentation and metrology go back at least to the 1800's. There are several good reasons to use optical frequencies, and with the scientific and technological advances of the last century: relativity, quantum mechanics, electronics, coherent microwave sources, lasers etc. we now have optical frequency references with truly exceptional performance. Optical atomic frequency references (OFR) were developed out of basic scientific explorations in precision spectroscopy of atoms and molecules. They now see numerous scientific applications, serve as the realization of base unit of length (the SI meter) and as practical tools for dimensional metrology. Over the last 100 years the frequency accuracy of OFR has improved about nine orders of magnitude, from 6 digits achievable with discharge lamps to modern frequency stabilized lasers referenced to laser cooled atoms that have frequency reproducibility of about 15 digits.
Journal of Physics B-Atomic Molecular and Optical Physics


Einstein, lenghth metrology, optical frequency references, speed of light, tests of relativity


Hollberg, L. , Oates, C. , Wilpers, G. , Hoyt, C. , Barber, Z. , Diddams, S. , Oskay, W. and Bergquist, J. (2005), Optical frequency / wavelentgh references, Journal of Physics B-Atomic Molecular and Optical Physics, [online], (Accessed April 18, 2024)
Created April 25, 2005, Updated February 19, 2017