Photovoltaics from first principles

It has been realized in recent years that the efficiency limits for single-junction solar cells can easily be overcome by a number of new design elements, involving plasmonic photonic crystals, plasmonic nanoparticles and up/down-conversion layers. We present a numerical method to analyze the formation of electron-hole pairs in these new types of solar cells, based on density functional theory and the Bethe-Salpeter equation. After discussing the main results of a typical numerical study, we suggest possible extensions and their implementation in typical device modeling programs.