Electron-lattice relaxation phenomena in halide perovskites

Halide perovskites (HaPs) have shown great promise as materials for use in energy and optoelectronic devices owing to their fascinating microscopic properties. Of particular scientific interest is the coupling of electronic to lattice-dynamical properties of HaPs, because a comprehensive understanding of it is key to predicting and further improving charge-carrier mobility and defect characteristics. In this talk, I will present our recent theoretical findings on electron-lattice relaxation phenomena in HaPs. Specifically, using molecular dynamics in conjunction with electronic-structure theory, it will be shown that the soft, polar lattice of paradigmatic HaPs leads to a range of very interesting electron-lattice relaxation effects. These include structural anharmonicities, nonlinear electron-phonon couplings and short-range correlated disorder potentials. The impact of these phenomena on charge-carrier mobilities, optical absorption and defect characteristics will be discussed.