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Colloquia & Guest Speakers


Ultra-Stable Photonic Integrated Sub-Hz Fundamental Linewidth Brillouin Lasers and Their Applications

Dr. Dan Blumenthal, University of California at Santa Barbara

Monday, April 8, 2019
3:30 p.m.
Goergen 101

Dan Blumenthal


Ultra-narrow linewidth, ultra-low phase noise and ultra-high frequency stability lasers serve as the heart of precision high-end scientific systems used in time-keeping, positioning, quantum and spectroscopy. However, these lasers are relegated to the domain of table top and fiber lasers systems and employ sophisticated optical reference cavities. Implementing lasers with this level of performance in a photnoic integrated platform opens the possibility to reduce the cost, size and power, reduce sensitivity to environmental conditions, and make this technology available to a wide range of new applications. In this talk, a new class of photonic integrated ultra-low linewidth and stability laser will be described. The laser is a stimulated Brillouin scattering (SBS) laser, capable of sub-Hz fundamental linewidth emission, fabricated in an ultra-low loss silicon nitride waveguide platform. The underlying physics, design, fabrication and performance of this laser will be covered. Reduction of the integral linewidth and close-to-carrier noise using miniature and integrated reference stabilization cavities will be described as will improving the long term frequency drift and fractional frequency stability to unprecedented levels for integrated lasers. Applications and new research projects that leverage the laser performance and stability will be described including chip-scale atomic clocks and a new frequency stable coherent optical transmission based link for low-energy scalable data center interconnects (FRESCO).


Daniel J. Blumenthal received the Ph.D. degree from the University of Colorado, Boulder (1993), the M.S.E.E. from Columbia University (1988) and the B.S.E.E from the University of Rochester (1981). He is currently a Professor in the Department of ECE at UCSB, Director of the Terabit Optical Ethernet Center (TOEC) and heads the Optical Communications and Photonics Integration (OCPI) group ( Dr. Blumenthal is Co-Founder of Packet Photonics Inc. and Calient Networks, manufacturers of optical communications and network equipment. He holds 22 patents and has published over 425 papers in the areas of Optical communications and optical packet switching, ultra-narrow linewidth integrated lasers, optical gyro sensors, InP, Silicon Photonic, and ultra-low loss silicon nitride waveguide photonic integration, photonic molecules, nano-photonic devices, microwave photonics. He is co-author of Tunable Laser Diodes and Related Optical Sources (New York: IEEE–Wiley, 2005) and has published in the Proceedings of the IEEE. He is a 2017 Fellow of the National Academy of Inventors (NAI), Fellow of the IEEE and Fellow of the Optical Society of America. He has served on the Board of Directors for National LambdaRail (NLR) and as an elected member of the Internet2 Architecture Advisory Council. He is recipient of a Presidential Early Career Award for Scientists and Engineers (PECASE), a National Science Foundation Young Investigator Award (NYI) and an Office of Naval Research Young Investigator Program (YIP) Award and has served on numerous program committees including OFC, Photonics in Switching and as guest editor of multiple IEEE Journal special issues.

Location: Goergen 101

Refreshments will be served.