Understanding the Electronic Structure of Novel Electronic Materials using Many-Body Perturbation Theory

Two important, and at first glance disparate, theoretical challenges in the understanding of modern electronic materials are: (1) the electronic structure of the interface between an organic material and an inorganic conductor or semiconductor and its relation to transport phenomena across the interface, and (2) the electronic structure of novel magnetic materials and its relation to the mechanisms of magnetic interaction in such materials. Unfortunately, further theoretical progress based on the density functional theory (DFT) framework is hampered by two limitations of currently available DFT: the need to describe localized and delocalized electronic orbitals on the same footing, and the need to consider filled and empty electronic states equally. This project will overcome these difficulties by turning to many-body perturbation theory, specifically to using the GW approximation for computing quasi-particle excitation energies. The results will significantly help to elucidate pressing issues in the understanding of the electronic structure of organic/inorganic interfaces, novel magnetic materials, and their relations to transport phenomena and magnetic coupling mechanisms, respectively.