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Physical Measurement Laboratory /Time and Frequency Division

Precision Photonic Synthesis Group

The Precision Photonic Synthesis Group conducts cutting-edge research and development of femtosecond laser frequency combs and frequency-stable lasers, allowing for extremely accurate measurements of optical frequencies, coherent frequency synthesis from the optical to the rf, microwave, and millimeter-wave domains, as well as optical spectroscopy with unprecedented precision.

fiber optical frequency comb
Femtosecond-Laser Frequency Combs for Optical Clocks
solar spectrum
Bringing the SI to Global Atmospheric Greenhouse Gas Measurement

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, user-defined optical waveform generation, and calibration of astronomical spectrographs for searches for exo-planets. We also develop photonic links to superconducting circuit platforms, bringing the bandwidth and exquisite timing of optical systems to quantum information systems and quantum-based voltage standards.

Projects and Programs

Compact ultrastable optical references illustration

Compact Ultrastable Optical References

Ongoing
At the heart of any stable laser is a reference cavity resonator. By locking a laser’s frequency to a reference cavity mode, the laser inherits the resonator’s stability. These stable lasers can then be used in various sensing and spectroscopy applications, including in optical atomic clocks and
Cryogenic Photonic Interconnects illustration

Cryogenic Photonic Interconnects

Ongoing
Microwave photonics, where optical systems are employed to transport, filter, generate, or otherwise process microwave and millimeter wave signals, takes advantage of the large bandwidth, low loss, and low noise of optical systems, as well as the long reach of optical fiber interconnects. We are

Femtosecond-Laser Frequency Combs for Optical Clocks

Ongoing
The self-referenced optical frequency comb, which our NIST/University of Colorado collaboration first demonstrated in 1999, ushered in a revolution in optical frequency metrology. The frequency comb made it possible to directly count optical cycles with femtosecond resolution using a compact and
CombSpec1

Frequency Comb Spectroscopy

Ongoing
Erbium mode-locked fiber lasers are a mature technology that provide a means to build robust optical frequency combs centered near 1550 nm. One research focus of our group is to extend the optical bandwidth of Er fiber-based combs into the near- to mid-infrared wavelength region of 1000 to 5000 nm
lownoisemicrowave

Optical and Microwave Waveform Synthesis

Ongoing
A typical optical frequency comb consists of thousands to millions of phase coherent modes (the "teeth" of the comb) that can all be used to synthesize precisely controlled electromagnetic waveforms. Our main research thrust in this area has been focused on the generation of microwave and millimeter

News and Updates

Gray cylinder two inches in diameter, held in gloved fingers

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
View All News and Updates

Major Accomplishments

  • Developed stable optical reference cavities with volume < 10 mL for mobile optical clocks
  • Used one of our compact cavity systems for submarine cable monitoring, demonstrating improved sensitivity

Contacts

Group Leader

Project Leader

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