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Scott Diddams

Physicist and NIST Fellow

Scott Diddams is a Fellow of the National Institute of Standards and Technology (NIST) and an Adjoint Professor at the University of Colorado. He carries out experimental research in the fields of precision spectroscopy and metrology, nonlinear optics, microwave photonics and ultrafast lasers.  He received the Ph.D. degree from the University of New Mexico in 1996.  From 1996 through 2000, he did postdoctroral work at JILA, NIST and the University of Colorado.  Since 2000, Diddams has been a staff physicist at NIST.  Present research focuses on the development of optical frequency combs and their use in optical clocks, tests of fundamental physics, novel spectroscopy in the visible and mid-infrared, and ultralow noise frequency synthesis.  In recent years, special attention has been given to infrared frequency comb sources as well as high repetition rate laser-based and microresonator frequency combs, which are being explored for applications in clocks, frequency and waveform synthesis, and astronomy.  

Selected publications are below and a full list can be found here.


​​​​​​IEEE Rabi Award (2017)

Jacob Rabinow Award for Innovation (2014)

Moore Distinguished Scholar in Engineering and Applied Science, Caltech (2012-13)

Department of Commerce Silver Medal Award for Scientific/Engineering Achievement (2011)

Arthur S. Flemming Award (2010)

Fellow of Optical Society of America (2009)

Fellow of American Physical Society (2009)

European Frequency and Time Forum (EFTF) Young Scientist Award (2007)

Presidential Early Career Award for Scientists and Engineers (2003).

Department of Commerce Gold Medal Award for Scientific/Engineering Achievement (2001).

National Research Council Postdoctoral Fellow (1998-2000). 


Architecture for the photonic integration of an optical atomic clock

Zachary L. Newman, Vincent N. Maurice, Tara E. Drake, Jordan R. Stone, Travis Briles, Daryl T. Spencer II, Connor D. Fredrick, Qing Li, Daron A. Westly, Bojan R. Ilic, B. Shen, M.-G Suh, K. Y. Yang, C Johnson, D.M. S. Johnson, Leo Hollberg, K. Vahala, Kartik A. Srinivasan, Scott A. Diddams, John E. Kitching, Scott B. Papp, Matthew T. Hummon
Optical atomic clocks, which rely on high-frequency, narrow-line optical transitions to stabilize a clock laser, outperform their microwave counterparts by

Optimizing linearity in high-speed photodiodes

Josue Davila-Rodriguez, X. Xie, J. Zang, Christian J. Long, Tara M. Fortier, Holly F. Leopardi, Takuma Nakamura, J. C. Campbell, Scott A. Diddams, Franklyn J. Quinlan
Analog photonic links require high fidelity, high speed optical-to-electrical conversion for applications such as radio-over-fiber, synchronization at kilometer

Fully self-referenced frequency comb consuming 5 Watts of electrical power

Paritosh Manurkar, Edgar F. Perez, Daniel D. Hickstein, David R. Carlson, Jeffrey T. Chiles, Daron A. Westly, Esther Baumann, Scott A. Diddams, Nathan R. Newbury, Kartik A. Srinivasan, Scott B. Papp, Ian R. Coddington
We present a hybrid fiber/waveguide design for a 100-MHz frequency comb that is fully self- referenced and temperature controlled with less than 5 W of

An electro-optic ultrafast light source with sub-cycle stability

David R. Carlson, Daniel D. Hickstein, Wei Zhang, Andrew J. Metcalf, Franklyn J. Quinlan, Scott A. Diddams, Scott B. Papp
Optical frequency combs can produce femtosecond light pulses with sub-cycle precision, and are typically made by relying on the intrinsic stability of mode
Created March 26, 2019, Updated September 30, 2019