Nanophotonics with two-dimensional atomic crystals

Electronic and photonic devices based on two-dimensional (2D) atomic crystals, such as graphene and layered transition-metal dichalcogenides (TMDCs), are perceived as potential candidates to complement, or even replace, conventional semiconductor devices in various applications. 2D crystals are of high material quality and stability, even so, they can be produced with large-area dimensions and at low cost. Moreover, the possibility of stacking different atomically-thin 2D layers on top of each other provides the opportunity of creating “artificial” designer materials, so-called van der Waals heterostructures. In this paper, optoelectronic devices based on 2D materials will be presented. We will discuss photodetection, light emission and photovoltaic energy conversion in 2D monolayers and van der Waals heterojunctions.