Optomechanics in the quantum regime with silicon nanostructures
Speaker: Amir Safavi-Naeini, California Institute of Technology
Series: Electrical Engineering Departmental Seminar
Location: Engineering Quadrangle B205
Date/Time: Monday, April 1, 2013, 4:30 p.m. - 6:00 p.m.
Mechanical resonators are the most basic and ubiquitous physical systems known. In on-chip form, they are used to process high frequency signals in every cell phone, television, and laptop. They have also been a critical part of progress in quantum information sciences in the last few decades in different shapes and forms, with kilogram-scale mirrors for gravitational wave detection measuring motion at its quantum limits, and the motion of single ions being used to link qubits for quantum computation.
In this talk, I will present our recent work with mechanical systems in the megahertz to gigahertz frequency range, formed by nanofabricating novel photonic/phononic structures on a silicon chip. These structures are designed to have both optical and mechanical resonances, and laser light is used to address and manipulate their motional degrees of freedom through radiation pressure forces. We laser cool these mechanical resonators to their ground states , and observe for the first time the quantum zero-point motion of a nanomechanical resonator . Conversely, we show that engineered mechanical resonances drastically modify the optical response of our structures, creating large effective optical nonlinearities not present in bulk silicon. We experimentally demonstrate aspects of these nonlinearities by observing 'electromagnetically induced transparency' and light slowed down to 6 m/s [3-4], as well as wavelength conversion [5-6], and generation of nonclassical optical radiation .
 J. Chan et al. "Laser cooling of a nanomechanical oscillator into its quantum ground state." Nature 478.7367 (2011): 89-92.
 ASN et al. "Observation of quantum motion of a nanomechanical resonator." Physical Review Letters 108.3 (2012): 33602.
 ASN, et al. "Electromagnetically induced transparency and slow light with optomechanics." Nature 472.7341 (2011): 69-73.
 ASN et al., in preparation.
 ASN, and O Painter. "Proposal for an optomechanical traveling wave phononphoton translator." New Journal of Physics 13.1 (2011): 013017.
 J.T. Hill, ASN, et al, Nature Communications 3 (2012), 1196.
 ASN, et al., "Squeezed light from an optomechanical resonator", in preparation.
Amir Safavi-Naeini is Ph.D. candidate in Applied Physics at the California Institute of Technology working in the group of Prof. Oskar Painter. He received his B.A.Sc. in Electrical Engineering (1st rank) from the University of Waterloo in Waterloo, Canada, where he worked briefly as a DSP engineer at RIM (now Blackberry), and Altera. He also worked as a summer research assistant at the Institute of Quantum Computing. Before starting at Caltech in 2008 as an NSERC graduate fellow, Amir spent one year at École Polytechnique Fédérale de Lausanne (EPFL), studying engineering and physics and designing photonics crystal cavities in the group of Prof. Kapon. Amir's recent research has centered on design, fabrication, and measurement of optomechanical resonators. His contributions have been featured in numerous magazines, including the New Scientist, Physics Today, APS Physics, Science Magazine, Science Daily, Nature, and Nature Photonics.