Enhancing Light-matter Interaction in Ultrathin Films using Optical Nanostructures

Abstract

Ultrathin films including two-dimensional materials and transparent conductive oxide nano-films are excellent candidates for future optoelectronic devices. However, external quantum efficiencies of the ultrathin film-based devices are typically limited due to their small physical thickness. The practical application of these ultrathin films therefore requires integration with optical nanostructures to enhance light-matter interaction in the thin films. In this work, I will present my efforts to modify the interaction between light and ultrathin films using different approaches, including hot electron injection, integration with Fano-resonant photonic crystals, and use a hybrid mode combining an epsilon-near-zero mode with a Huygens’ dielectric metasurface. The optoelectronic devices demonstrated based on these integrations result in significant increases in absorption, photoresponsivity, and modulation depth.