Abstract

Monolayer transition-metal dichalcogenides (TMDs) have recently emerged as fascinating novel materials. Like graphene, they can easily be exfoliated from bulk crystals. Unlike graphene, they have a large and direct band gap, making them attractive for potential applications in electronics or optoelectronics. They may also allow for novel device functionalities, as the spin and valley pseudospin degrees of freedom are directly coupled and stabilized by a large spin splitting in the conduction and valence bands. The optical properties of these two-dimensional crystals are dominated by tightly bound electron-hole pairs (excitons) and more complex quasiparticles such as charged excitons (trions) and biexcitons.

© 2017 IEEE