OSC Colloquium: Garrett D. Cole

    Thursday, October 11, 2018 - 3:30pm - 5:00pm
    Meinel 307

    1630 E. University Blvd.

    3rd Floor Lobby area

    Host: Dal Wilson


    Open to campus and public.


    Speaker: Garrett D. Cole

    Topic: Substrate-transferred crystalline coatings

    Visit our website for future lecture dates and speaker information: http://www.optics.arizona.edu/news-events/events/colloquium For a list of our archived lectures: http://www.optics.arizona.edu/news-events/events/colloquium/archive


    Substrate-transferred crystalline coatings are a groundbreaking new concept in optical interference coatings. Building upon fundamental research in optomechanical resonators, these “semiconductor supermirrors” were first demonstrated in 2013, with the key advantage being the ability to simultaneously achieve ultralow levels of optical and mechanical losses. With continuous refinement in epitaxial growth and layer transfer, we have now realized significant improvements in the limiting performance of these novel single-crystal GaAs/AlGaAs multilayers. In the near-infrared (NIR), for center wavelengths spanning 1064 to 1560 nm, we have reduced the scatter + absorption losses to <3 parts per million (ppm), enabling a cavity finesse exceeding 600,000 (equivalent to a reflectance >99.9995%) at the telecom-relevant wavelength range near 1550 nm. Investigations in the mid-IR (MIR) spectral region also show exceptionally low levels of losses, with measurements yielding absorption as low as 2 ppm at 3700 nm. Taken together, our NIR coatings are now fully competitive with ion beam sputtered films, while our first prototype MIR optics have reached state-of-the-art performance levels for reflectors covering this portion of the fingerprint region for optical gas sensing. Thus, mirrors fabricated via our unique direct bonding technique exhibit the lowest mechanical loss (and thus Brownian noise), the highest thermal conductivity, and, the widest spectral coverage of any supermirror technology. Looking ahead, we see a bright future for crystalline coatings in applications requiring the ultimate levels of optical, thermal, and optomechanical performance, from reference cavities for optical atomic clocks to multi-band reflectors for kW-class laser machining systems.

    Speaker Bio(s): 

    Garrett D. Cole, Co-Founder of Crystalline Mirror Solutions (http://www.crystallinemirrors.com/), obtained his PhD in Materials from the UCSB in 2005. Since completing his doctorate, he has held positions ranging from the first employee of a high-tech startup (Aerius Photonics LLC, now FLIR Electro-Optical Components), to a postdoctoral position at Lawrence Livermore National Laboratory, a Marie Curie Fellow of the Austrian Academy of Sciences, and a university assistant in the Faculty of Physics at the University of Vienna. Dr. Cole has co-authored 2 book chapters and published more than 50 journal articles and conference proceedings including papers in Science, Nature, Nature Physics, Nature Photonics, Nature Nanotechnology, Nature Communications, Physical Review Letters, and the Proceedings of the National Academy of Sciences. Leveraging his expertise in micro- and nanofabrication, tunable semiconductor lasers, and cavity optomechanics, Dr. Cole, together with Professor Markus Aspelmeyer, founded Crystalline Mirror Solutions, a photonics start-up commercializing high-performance optics for laser-based metrology and manufacturing systems.

    Garrett D. Cole is hosted by Dal Wilson



    Refreshments 3:30pm

    Lecture @ 3:45pm - 5pm