Speaker: Karim Achouri
Affiliation: Post-Doc, Ecole Polytechnique de Montréal, Canada
Abstract: An electromagnetic metasurface is a two-dimensional structure that is thin with respect to the considered wavelength of operation. It is used to control the scattering of electromagnetic waves. Such a structure is conventionally composed of a periodic arrangement of engineered subwavelength scattering particles. It enables one to control the amplitude, phase, polarization and direction of propagation of the fields reflected and transmitted by the metasurface, when the latter is illuminated by a specific incident field.
This presentation presents an overview of the general mathematical synthesis framework developed by the author. Contrary to other previous synthesis methods, the one discussed here is based on rigorous zero-thickness sheet transitions conditions, which provides an unprecedented physical perspective of the electromagnetic properties of metasurfaces. It yields the metasurface susceptibilities as functions of specified arbitrary electromagnetic transformations. Additionally, the numerical analysis and the practical realization of metasurfaces, which are based upon that synthesis method, will also be discussed.
Finally, several metasurface concepts and applications will be presented, which notably include: birefringent polarization beam splitter and orbital angular momentum generator, bianisotropic perfect refractors, coherent spatial modulators, nonreciprocal nongyrotropic screen, metasurface cavities for light extraction and spontaneous emission rate enhancement of single-photon sources and nonlinear metasurface exhibiting nonreciprocal second-harmonic generation.
Biography: Karim Achouri was born on May 22, 1988, in Lausanne, Switzerland. He received his B.S. in microengineering and his M.S. in photonics and applied optics, as well as a minor in space technologies, from the Swiss Federal Institute of Technology in Lausanne (EPFL), Switzerland, in 2010 and 2012, respectively. In 2013, he joined the Polygrames research center where he is currently working towards the Ph.D. degree at the Ecole Polytechnique de Montréal, Canada. His research interests are in the areas of electromagnetics, metamaterials, applied optics, photonics and nanotechnologies. His most recent work is on the mathematical synthesis, the numerical analysis and the practical realization of electromagnetic metasurfaces and their applications. This work covers a broad range of topics including birefringence, bianisotropy, nonreciprocity and nonlinearity, with concepts applying to both the microwave and the optical regimes.
For more information, contact Prof. Aydogan Ozcan ()
Date(s) - Jul 20, 2017
10:00 am - 11:00 am