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Optical Frequency Measurements Group

           Fs-laser Frequency Combs                Neutral Atom Optical Clocks 

The Optical Frequency Measurements Group conducts cutting-edge research focused on generating stable optical frequencies and developing tools for measuring optical frequencies precisely. We construct different types of atomic clocks to generate optical frequencies that have demonstrated instabilities of less than 1 Hz (fractionally, 10-15) in 1 second averaging time, and absolute fractional frequency uncertainty approaching 10-16. We develop mode-locked fs-laser frequency combs to connect stable optical frequencies to each other and to microwave sources with an imprecision approaching 1 part in 1019. These state-of-the-art frequency combs are also developed for other important applications, including ultra-low noise microwave generation, mid-IR molecular spectroscopy, microcomb generation, optical waveform generation,and calibration of astronomical spectrographs for searches for exo-planets. Visit the links for more information.

Neutral Atom Optical Clocks

Fs-laser Frequency Combs


Time and Frequency Division
National Institute of Standards and Technology
Mail Stop 847.10
325 Broadway
Boulder, CO 80305-3334

Name Position Phone
Chris Oates Group Leader 303-497-7654
Scott Diddams Project Leader 303-497-7459
Richard Fox Project Leader 303-497-3478
Andrew Ludlow Project Leader 303-497-4972