Colloquium: Scott Diddams

    Date: 
    Thursday, April 5, 2018 - 3:30pm - 5:00pm
    Location: 
    Meinel 307
    Description: 

    Synthesizing Light

    Abstract(s): 

    Frequency synthesis is ubiquitous in all aspects of our modern technological society, with examples being found in wide ranging applications from computing, communications and navigation systems to sensors and scientific instrumentation. Historically, the generation and precise control of electromagnetic radiation has been confined to the radio frequency and microwave domains, but “light gears” based on optical frequency combs provide the opportunity to dramatically expand the synthesis bandwidth to cover the entire terahertz and optical domains as well.  In this talk, I will describe the laser and photonic tools we use to synthesize light with precise control over its phase and frequency.  This is the basis of a new generation of optical clocks that now track time to 18 digits, as well as the driver of applications we are pursing in fields ranging from infrared trace gas sensing to astronomy. Finally, I will present light synthesizers based on parametric oscillation in low-loss microresonators. Such miniature devices open the possibility for optical frequency synthesis on a photonic-integrated-chip that will be an enabler of future technological and scientific advances.

    Speaker Bio(s): 

    Scott Diddams is a Fellow of the National Institute of Standards and Technology (NIST) where 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.  Together with colleagues at JILA, he built the first self-referenced, octave-spanning optical frequency comb and used it to produce carrier-envelope phase stabilized pulses.  Since 2000, Diddams has been a research physicist at NIST and is the leader of the Optical Frequency Measurements group.  He has continued the development of optical frequency combs and pioneered 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 microwave photonics and astronomy.  Dr. Diddams was a recipient of the Department of Commerce gold and silver medals for "revolutionizing the way frequency is measured” as well as the Presidential Early Career Award in Science and Engineering (PECASE) for his work on optical frequency combs. He is a Fellow of the Optical Society of America and the American Physical Society, and a Professor Adjoint at the University of Colorado.