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David Long (Fed)

Project Leader

Nature Photonics cover
Ultrafast dual-comb spectroscopy
An artistic image of a dual-frequency comb that is generated by using an optical parametric oscillator to convert a pair of near-infrared combs into the mid-infrared. The generated combs enable nanosecond-timescale spectroscopy for probing the ultrafast dynamics found in supersonic gas jets, explosions and chemical kinetics.
Credit: Image: Brad Baxley, Part to Whole, LLC. Cover Design: Bethany Vukomanovic

David Long received his PhD in chemistry from the California Institute of Technology under the guidance of Mitchio Okumura. He then moved to the National Institute of Standards and Technology where he is currently a project leader in the Photonics and Optomechanics group.

Dr. Long’s research has focused on the development and application of ultrasensitive spectroscopic methods to present problems in remote sensing, atmospheric chemistry, optomechanics, and quantum science. Electro-optic frequency combs have been a particular focus of his work and have been applied in areas such as physical metrology, ultrafast dynamics, and atomic sensing. Recent efforts have transitioned these approaches to chip scale, integrated photonic platforms as well as demonstrated spectral translation of these combs throughout the visible and mid-infrared through the use of optical parametric oscillation.

Dr. Long’s work has been recognized by a number of awards including the Presidential Early Career Award for Scientists and Engineers, the National Science Foundation Graduate Fellowship, the Department of Commerce Silver Medal, the Sigma Xi Young Scientist Award, the National Defense Science and Engineering Fellowship, the Barry M. Goldwater Scholarship, and the Morris K. Udall Scholarship.

Research Interests

  • Optical frequency combs
  • Molecular spectroscopy
  • Integrated photonics
  • Physical sensing
  • Nonlinear optics
  • Quantum science



Nanosecond time-resolved dual-comb absorption spectroscopy

David Long, Matthew Cich, Carl Mathurin, Garrett Mathews, Adam Heiniger, Augustine Frymire, Gregory Rieker
Frequency combs have revolutionized the field of optical spectroscopy, enabling researchers to probe molecular systems with a multitude of accurate and precise

Optical-cavity-based primary sound standard

Akobuije Chijioke, Richard A. Allen, Steven E. Fick, David Long, Benjamin Reschovsky, Jared Strait, Randall P. Wagner
We propose an optical sound standard in which the sound pressure is directly measured by using an optical cavity to observe the induced change in the refractive

Intrinsically accurate sensing with an optomechanical accelerometer

Benjamin Reschovsky, David Long, Feng Zhou, Yiliang Bao, Richard A. Allen, Jason J. Gorman, Thomas W. LeBrun
We demonstrate a microfabricated optomechanical accelerometer that is capable of percent-level accuracy without external calibration. To achieve this capability

Patents (2018-Present)

Direct Digital Chirp Synthesizer And Generating A Chirped Optical Frequency Comb

NIST Inventors
David Long and Benjamin Reschovsky
Disclosed is a direct digital chirp synthesizer for generating a chirped optical frequency comb that includes: a direct digital synthesizer that receives a repetition frequency signal from a delay generator, receives a clock frequency from a frequency converter, produces a radiofrequency chirp

Optomechanical Accelerometer And Performing Optomechanical Accelerometry

NIST Inventors
Jason J. Gorman , Thomas W. LeBrun and David Long
An optomechanical accelerometer includes: a fiducial mass for a microscale Fabry-Perot optical cavity; a proof mass for the microscale Fabry-Perot optical cavity, such that the proof mass oscillates in a displacement motion toward and away from the fiducial mass in response to acceleration of the

Optomechanical Ultrasound Detector And Performing Ultrasound Imaging

NIST Inventors
David Long , Thomas W. LeBrun and Jason J. Gorman
An optomechanical ultrasound detector includes: a micromirror substrate; a mechanical resonator that receives ultrasound waves, oscillates at resonator frequency f.sub.r, changes cavity length L.sub.c, and produces intra-cavity light; and an optical microcavity between the micromirror substrate and
Created September 10, 2019, Updated February 20, 2024