Dresden 2017 – wissenschaftliches Programm
MM 41: Electronic Structure Theory: New Concepts and Developments in Density Functional Theory and Beyond - IV
MM 41.1: Hauptvortrag
Mittwoch, 22. März 2017, 10:30–11:00, GER 38
Electronic excitations in 2D materials and heterostructures — •Kristian Sommer Thygesen — Technical University of Denmark, Lyngby, Denmark
Atomically thin two-dimensional (2D) materials have recently emerged as a new class of materials with unique and highly tunable opto-electronic properties. Different 2D crystals can be stacked to form van der Waals heterostructures (vdWH) where the individual 2D layers are held together by weak van der Waals forces leading to atomically well-defined interfaces. This fascinating scenario opens up the possibility of designing heterostructures with tailored electronic or optical properties. I will give a general introduction to the electronic properties of 2D materials, including characteristic features of their dielectric screening and collective excitations with special emphasis on the challenges related to their ab-initio description. I will show how the dielectric function of a given 2D material can be controlled by embedding it into a vdWH, and how this in turn can be used to control the band structure, exciton binding energies or the plasmon dispersion in 2D materials.