Dielectric Genome of van der Waals Heterostructures

• Published in: Nano letters Vol. 15; no. 7; pp. 4616 - 4621
• Main Authors: Andersen, Kirsten, Latini, Simone, Thygesen, Kristian S
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 08-07-2015
• Subjects: van der Waals heterostructures; excitons; dielectric function; 2D materials; density functional theory; plasmons
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/acs.nanolett.5b01251

Vertical stacking of two-dimensional (2D) crystals, such as graphene and hexagonal boron nitride, has recently lead to a new class of materials known as van der Waals heterostructures (vdWHs) with unique and highly tunable electronic properties. Ab initio calculations should in principle provide a powerful tool for modeling and guiding the design of vdWHs, but in their traditional form such calculations are only feasible for commensurable structures with a few layers. Here we show that the dielectric properties of realistic, incommensurable vdWHs comprising hundreds of layers can be efficiently calculated using a multiscale approach where the dielectric functions of the individual layers (the dielectric building blocks) are computed ab initio and coupled together via the long-range Coulomb interaction. We use the method to illustrate the 2D–3D transition of the dielectric function of multilayer MoS2 crystals, the hybridization of quantum plasmons in thick graphene/hBN heterostructures, and to demonstrate the intricate effect of substrate screening on the non-Rydberg exciton series in supported WS2. The dielectric building blocks for a variety of 2D crystals are available in an open database together with the software for solving the coupled electrodynamic equations.