Research Fellows Directory
Dr Johannes Lischner
Imperial College London
The goal of my research is to advance the understanding of electronic excitations in materials. To achieve this, I develop parameter-free quantum-mechanical theories that allow for the modeling of fascinating phenomena that are out of reach of current state-of-the-art approaches, such as ab initio density-functional theory or the GW approach. In particular, I have recently developed a new method to describe the interaction of electrons with plasmons in materials and used this approach to understand spectroscopic experiments in nanomaterials, such as photoemission experiments on doped graphene or tunneling measurements on quantum-well two-dimensional electron gases. I also developed a new method to determine the coupling strength of electrons to spin fluctuations and investigated the question if this coupling can give rise to unconventional high-temperature superconductivity in the recently discovered iron pnictides and chalcogenides.
Electronic excitations also play an important role in energy technology. I am currently developing computational tools to study electronic excitations at solid-liquid interfaces for photoelectrochemical applications, such as dye-sensitized solar cells or photosynthetic cells for the splitting of water. For this, I construct multi-scale approaches, which employ highly accurate quantum-mechanical electronic structure methods to describe an active subsystem (typically, the electrode) and coarse-grained continuum methods to model the complex liquid environment.