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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

Projects and Programs

Microresonator Device Research

With micro-resonators (fabricated in house or by collaborators) we are developing microcombs, integrated reference cavities and low-noise laser sources. The

Calcium Thermal Beam Optical Clock

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

Publications

Terahertz-Rate Kerr-Microresonator Optical Clockwork

Author(s)
Tara E. Drake, Travis Briles, Daryl T. Spencer II, Jordan R. Stone, David R. Carlson, Daniel D. Hickstein, Qing Li, Daron A. Westly, Kartik A. Srinivasan, Scott A. Diddams, Scott B. Papp
Kerr microresonators generate interesting and useful fundamental states of electromagnetic radiation through nonlinear interactions of continuous-wave (CW)

Self-organized nonlinear gratings for ultrafast nanophotonics

Author(s)
Daniel D. Hickstein, David R. Carlson, Haridas Mundoor, Jacob B. Khurgin, Kartik A. Srinivasan, Daron A. Westly, Abijith S. Kowligy, Ivan I. Smalyukh, Scott A. Diddams, Scott B. Papp
We present the first demonstration of automatically quasi-phase-matched second-harmonic generation using femtosecond pulses. The high-confinement geometry of

Towards the optical second: verifying optical clocks at the SI limit

Author(s)
William F. McGrew, Xiaogang Zhang, Robert J. Fasano, Holly Leopardi, Daniele Nicolodi, Kyle P. Beloy, Jian Yao, Jeffrey A. Sherman, Stefan A. Schaeffer, Joshua J. Savory, Stefania Romisch, Christopher W. Oates, Thomas E. Parker, Tara M. Fortier, Andrew D. Ludlow
The pursuit of ever more precise measures of time and frequency motivates redefinition of the second in terms of an optical atomic transition. To ensure

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