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Optical Frequency Measurements Group

The Optical Frequency Measurements Group conducts cutting-edge research focused on generating stable optical frequencies and developing tools for precisely measuring optical frequencies, which have the potential to achieve unprecedented timing performance.

We construct different types of atomic clocks to generate optical frequencies that have demonstrated a fractional instability approaching 1 part in 1018 and an absolute fractional frequency uncertainty below 10-17. We develop laser frequency combs to connect stable optical frequencies to each other and to microwave sources with an imprecision below 1 part in 1019. These state-of-the-art frequency combs are also developed for other important applications, including ultra-low noise microwave generation, chip-scale sensors, mid-IR molecular spectroscopy, optical waveform generation,and calibration of astronomical spectrographs for searches for exo-planets.

News and Updates

Spotlight: Astro-Etalon

A small role can make an astronomical impact, as is the case for a tiny NIST-built piece of a new planet-hunting project from NASA and the National Science

Projects and Programs

Calcium Thermal Beam Optical Clock

Ongoing
A simple, compact alternative to the highest performing optical standards, the Ca clock uses a thermal beam of neutral atoms with one or two lasers to achieve

Frequency Comb Spectroscopy

Ongoing
We use frequency combs based on ultrafast mode-locked lasers to perform precision spectroscopy in the near- and mid-infrared domains, for rapid, high

Publications

Thermal-light heterodyne spectroscopy with frequency comb calibration

Author(s)
Scott Diddams, Connor Fredrick, Franklyn Quinlan, Ryan Terrien, Suvrath Mahadevan, Freja Olsen
Precision laser spectroscopy is key to many developments in atomic and molecular physics and the advancement of related technologies such as atomic clocks and

Broadband stability of the Habitable Zone Planet Finder Fabry-Pérot etalon calibration system:evidence for chromatic variation

Author(s)
Ryan C. Terrien, Joe P. Ninan, Scott Diddams, Suvrath Mahadevan, Samuel Halverson, Chad Bender, Connor Fredrick, Fred Hearty, Jeffrey M. Jennings, Andrew J. Metcalf, Andrew J. Monson, Arpita Roy, Christian Schwab, Gudmundur Stefansson
The comb-like spectrum of a white light-illuminated Fabry-Pérot etalon can serve as a cost-effective and stable reference source for precise Doppler

Single-cycle all-fiber frequency comb

Author(s)
Sida Xing, Daniel Lesko, Takeshi Umeki, Tsung Han Wu, Alexander Lind, Nazanin Hoghooghi, Scott Diddams
Broad bandwidth mid-infrared frequency combs are important for molecular spectroscopy in a wide range of fundamental and applied research. However, realization

Awards

NRC Postdoc Program

Apply for an NRC postdoc in optical atomic clock or fs-laser frequency comb research. Application deadlines are February 1 and August 1 annually (but inquire well in advance).

Postdoc and Student Opportunities

Summer Undergraduate Research Fellowship (SURF): Summer program at NIST-Boulder for undergraduates in science, engineering, and mathematics. The application deadline is February 15 annually.

Postdoctoral, Visiting Scientist, and Graduate Positions: Our group has periodic openings for Postdoctoral Fellows, Visiting Scientists, and Graduate Students. Please contact us for more information.

Contacts

Group Leader

Project Leaders