Colloquia & Guest Speakers
Novel Material Platforms for Metasurfaces and Metaphotonic Devices
Dr. Viktoriia Babicheva, Georgia State University
Monday, January 23, 2017
Goergen Hall, Room 101
Optical metamaterials are three-dimensional structures with rationally designed building blocks that enable devices with distinct optical responses not attainable with naturally available materials. In turn, optical metasurfaces comprising a class of metamaterials with a reduced dimensionality allow the miniaturization of conventional refractive optics into planar structures. Such a planar photonics technology is expected to facilitate new physics and enhanced functionality for devices that are distinctly different from those observed in their three-dimensional analog. In this talk, I will show that nanostructures made of high-index dielectric materials, such as silicon, transition metal dichalcogenides, or hexagonal boron nitride, support optically induced both electric and magnetic resonances in the visible and near-infrared spectral ranges. I will present our results on antireflective properties of metasurfaces based on high-index nanoparticle arrays and explain how zero backscattering from the highly reflective substrate can be achieved.
Scattering-type scanning near-field optical microscope (s-SNOM) provides optical, chemical, and structural information of a metasurfaces and enables their imaging with nanoscale resolution. I will show our study of nanolayers of materials with different permittivities and demonstrate an approach to identify material type based on near fields at sample edges. The recent discovery of high-index materials that offer low loss and tunability in their optical properties as well as complementary metal-oxide-semiconductor (CMOS) compatibility can enable a breakthrough in the field of nanophotonics, optical metamaterials, and their applications.
Viktoriia Babicheva received her B.S. and M.S. degrees in Physics from Moscow Institute of Physics and Technology, Russia. As a Ph.D. student at the Technical University of Denmark, she worked on plasmonic waveguides and modulators as well as novel plasmonic materials, and she received her Ph.D. degree in Photonics Engineering 2013. Currently, she is a postdoc at Center for Nano-Optics at Georgia State University and her research interests are near-field imaging of nanostructures, all-dielectric metasurfaces, localized and delocalized surface plasmon resonances, and hyperbolic metamaterials.
Refreshments will be served.