Skip to main content
Loading Events

« All Events

  • This event has passed.

ECE Seminar – Professor Georgios Veronis, Louisiana State University

May 2 @ 3:00 PM 4:30 PM

Topological edge states at singular points and broadband switchable absorbers

Abstract: We introduce non-Hermitian plasmonic waveguide-cavity systems with topological edge states (TESs) at singular points such as exceptional points. The structure unit cells consist of a metal-dielectric-metal (MDM) waveguide side-coupled to MDM stub resonators with modulated distances between adjacent stubs. In such structures the modulated distances introduce an effective gauge magnetic field. We show that such structures achieve extremely high sensitivity of the reflected light intensity. TESs at singular points could lead to singularity-based plasmonic devices with enhanced performance. We also introduce multilayer structures with the phase-change material germanium-antimony-tellurium (GST) for use as broadband switchable absorbers in the infrared wavelength range. We use a memetic optimization algorithm coupled with the transfer-matrix method to optimize both the material composition and the layer thicknesses of the multilayer structures. We show that in the optimized structures near perfect absorption can be switched to very low absorption in a broad wavelength range by switching GST from its crystalline to its amorphous phase. Our results could pave the way to a new class of broadband switchable absorbers and thermal sources in the infrared wavelength range.

Georgios Veronis

Bio: Georgios Veronis received the B.S. degree from the National Technical University of Athens, Athens, Greece, in 1997, and the M.S. and the Ph.D. degrees from Stanford University, Stanford, CA, in 1999 and 2002, respectively, all in electrical engineering. From 2003 to 2007, he was an Engineering Research Associate at Ginzton Laboratory, Stanford University. Since 2008 he has been with the School of Electrical Engineering & Computer Science and the Center for Computation & Technology at Louisiana State University in Baton Rouge, LA, where he is currently a Professor. His research interests include the theory and simulation of photonic materials, nanoscale photonic devices, plasmonics, and computational electromagnetics. Dr. Veronis received the National Science Foundation Career Award in 2013, and is a Fellow of the SPIE.

1415 Engineering Drive
Madison, 53711
+ Google Map