Excitonic semiconductors on plasmonic substrates: optical and electronic effects

Abstract

Two-Dimensional (2D) chalcogenides of Mo and W are semiconductors that show strong excitonic responses due to their highly quantum-confined character. This talk will discuss our recent work on optical phenomena and electronic phenomena in 2D semiconductors when they are placed in close proximity on plasmonic substrates such as Au, Ag and Al. I will present how 1D nanostructuring of Mos2, WS2, WSe2 etc. into nanophotonic dielectric gratings can enable exploration of new regimes of light-matter confinement including formation of hybrid exciton-plasmon-polariton states. I will extend this concept to 2D hybrid pervoskites and superlattices. Finally, I will also show how using a plasmonic tip once can use near-field tip based micro-spectroscopy to probe defects, interfaces and hybrid states in 2D excitonic semiconductors