2D layered materials
Description / Outline
Two-dimensional (2D) layered materials are crystals with strong intralayer bonds but only weak, van-der-Waals type interlayer bonds, such as graphite, MoS2, or hexagonal boron nitride (hBN). They can be exfoliated to an atomically thin monolayer and stacked into heterostructures with almost arbitrary choice of combinations. Besides graphene, the most famous 2D materials are transition metal dichalcogenides (TMDCs) and specifically MoS2, MoSe2, WS2, and WSe2. These materials have intriguing optical and electronic characteristics. For example, they are indirect semiconductors in the bulk form but show strong excitonic emission in the visible range in their monolayer form. We are interested in their optical properties, including exciton-phonon coupling, and in their interactions in heterostructures with other layers.