Basic Theoretical and Numerical Concepts of Photovoltaics

Solar cell simulations have become an essential tool for the development of novel types of photovoltaic devices. Many of the standard software packages currently in use are very mature numerical tools, and solar cell device simulations make up for a good fraction of the literature about photovoltaics. We give an overview of the basic theoretical and numerical concepts underlying solar cell simulations, and we will work out a typical example to point out the advantages, but also some of the practical limitations of standard photovoltaic device simulations. In this context, we emphasize the role of first principles methods as ideal reference systems for device simulations. Finally, we pick up thermalisation as a typical topic, which goes beyond conventional solar cell simulations. We provide some insight into its complex underlying processes and discuss the implementation of thermalisation in conventional solar cell device simulations.