ECE Seminar: Accurate Modeling of Atomically Thin Layered Materials in Electromagnetic Wave Propagation and Scattering Problems
Monday, February 16, 2015
2:00 pm - 3:00 pm
Hudson Hall 216
Ergun Simsek, Assistant Professor of Electrical and Computer Engineering,The George Washington University
In the last decade, we have experienced transformational changes in the areas of plasmonics and two-dimensional (2D) materials. Plasmonics have taught us that we can beat the diffraction limit, dramatically enhance the electric field, and build extremely small, ultrafast, and low power consuming opto-electronic devices by using metal nanoparticles. Graphene, the vanguard of 2D materials, has proven that these 2D materials have unprecedented electrical, optical, and mechanical properties and they will play a crucial role in future opto-electronic technologies.Another field that grows so strongly is excitonics with 2D transition metal dichalcogenides (TMDs). Recent studies have proven that the excitonic properties of 2D TMDs differ from their bulk (3D) state. In contrast to bulk, the electron and hole forming an exciton in monolayer TMDs are strongly confined to the plane of the monolayer. Hence monolayer TMDs, which are direct-gap semiconductors with bandgaps in the visible regime, exhibit strong sub-bandgap photoexcitations at room temperature owing to weak dielectric screening and binding energies of at least several hundred meVs.