Engineering Optical Absorption in Graphene and Other 2D Materials: Advances and Applications

Abstract 2D materials are promising but remain to be further explored, with respect to their usage in various optoelectronic devices. Generally, 2D materials exhibit far less than ideal absorption due to their thickness, limiting their deployment in practical optoelectronic applications. To address this challenge, extensive research has been performed utilizing different designs, such as distributed Bragg reflector microcavities, metallic reflectors, photonic crystal nanocavities, and plasmonic nanostructures, to confine light within 2D materials and increase light absorption. Recent progresses in enhancing light absorption in graphene and other 2D materials such as transition metal dichalcogenides and phosphorene are reviewed. Some physical mechanisms that realize enhanced absorption in 2D materials, as well as their potential applications are also discussed.