Influence of excited states on the optical properties of low dimensional materials

• Applicant: Dr. Thorsten Deilmann
• Subject Area: Theoretical Condensed Matter Physics
• Term: Funded in 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 327744304

In the present project the optical properties of different materials (e.g. graphene nanoribbons, novel 2D materials and heterostructures) will be investigated theoretically using ab-initio methods. Based on the well established density functional theory the GW approximation is used to find a reliable spectrum for the ground state as well as for excited electronic states. On this basis the Bethe-Salpeter equation is solved to investigate coupled electron-hole states. This project goes beyond the commonly used methodology and extends it to include one additional electron or hole (excitation of trions). The resulting equations are solved, thus allowing for a direct comparison of the two- and three-particle excitations. In particular, the project aims to understand these excited states build up by two or three particles (electrons and holes) and the differences between them. Special attention will be given to the investigation within different environments. A further important goal is the search for further interesting materials which are suitable for opto-electronic devices.

• DFG Programme: Research Fellowships
• International Connection: Denmark
• Host: Professor Dr. Kristian Sommer Thygesen