Riding the light rail—harnessing optical forces on a silicon chip

Mo Li
University of Minnesota
Department of Electrical and Computer Engineering

Abstract - Nanomechanics and nanophotonics are among the most exciting areas of nanoscience. By generating and controlling a new type of gradient optical force in integrated photonic systems, we are able to seamlessly integrate these two fields together to form the new nano-optomechanical systems (NOMS). In this talk, we first demonstrate all-optical operation of nanomechanical resonators embedded in silicon waveguide circuits using optical forces. Further we experimentally prove the theoretical prediction that this waveguide optical force is bipolar – its direction can be tuned to be attractive or repulsive by changing the relative optical phase of coupled lightwaves. Subsequently, we show exploitation of optical forces in a variety of interesting optomechanical structures, including photonic crystal and micro-disk optical resonators. Harnessing the optical forces on a silicon chip enables new paradigms of nanophotonic and nanomechanical devices, such as all-optical switching, tunable nanophotonics, radio-frequency photonics and large-scale integration of NEMS.

Biography - Mo Li currently is an assistant professor in the Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities. From 2007 to 2010, he was a postdoctoral associate in Department of Electrical Engineering at Yale University. In 2007, he received his Ph.D. degree in Applied Physics from Caltech. His primary research interests are nano-electromechanical systems (NEMS), nanophotonics, nano-optomechanical systems (NOMS), quantum limited measurement and various sensing applications.