OSC Colloquium: Dr. Peter Rakich

    Thursday, October 21, 2021 - 3:45pm - 5:00pm
    Zoom & Meinel 307

    Title: Mixing Light and Sound Using Engineered Brillouin Interactions


    In recent years, acoustic phonons have emerged as a powerful resource for signal processing, precision metrology, and quantum information processing. In this talk, we explore methods for controlling and shaping the interactions between photons and acoustic phonons as the basis for both classical and quantum information processing applications. We begin by describing how traveling-wave photon-phonon coupling can be engineered within silicon-based optomechanical waveguides to realize a range of new Brillouin-based optomechanical interactions. Harnessing these interactions, we create non-reciprocal light propagation, optical amplifiers, and laser oscillators as the basis for new signal processing technologies in silicon photonics. We also show that anti-Stokes Brillouin scattering permits laser-based cooling of phonon modes as a means of controlling noise in Brillouin processes.

    Building on these concepts, we also explore intriguing new regimes of photon-phonon coupling at cryogenic temperatures, where intrinsic sources of phonon dissipation plummet.  Using Brillouin interactions to access high Q-factor bulk-acoustic phonon modes within macroscopic crystalline resonators, we demonstrate new methods to control of ultra-long-lived phonon modes that open the door to cryogenic phonon spectroscopy and new high frequency (10-100GHz) quantum optomechanical experiments.

    Speaker Bio(s): 

    Peter T. Rakich (Ph.D. Physics, MIT) is an Associate Professor of Applied Physics, and Physics, and is a member of the Yale Quantum Institute (YQI). He is a recent recipient of the Packard Fellowship for Science and Engineering as well as ONR’s Young Investigator Award for studies of the mechanical properties of light.  His research group focuses on topics ranging from nanophotonics and nonlinear optics to cryogenic phonon physics and the quantum properties of sound. He and his team have recently harnessed the mechanical properties of light to create silicon-based Brillouin amplification and Brillouin laser technologies in silicon. His group also works to develop quantum-acoustic memories, ultra-sensitive nonlinear spectroscopy methods, and new types of laser and oscillator technologies. Before he arrived at Yale, he was a Senior Member of the Technical Staff at Sandia National Laboratories (2008-2012), where he developed several new programs to harness engineerable nonlinear interactions in nanophotonic systems. He is an author of more than 50 peer-reviewed journal publications, on topics ranging from photonic crystals to optomechanics, to supercontinuum generation, to cryogenic phonon physics.