Electronic properties of perovskite absorbers for solar cell applications

Metal halide perovskite absorbers have captured the attention of the photovoltaics research community in the past 3 years, reaching efficiencies over 19\%. Despite this unprecedented progress, the remarkable physical properties of these materials are not yet fully understood. In this work we show an exhaustive computational study of CH$_3$NH$_3$PbI$_3$ within density functional theory and the GW approximation. We show the effect of semicore states and spin-orbit coupling on the quasiparticle band gap of CH$_3$NH$_3$PbI$_3$ and describe a straightforward ``self-consistent scissor'' method to correct the underestimated dielectric screening in the G0W0 approach [1]. Finally, we model the interplay between the structural and electronic properties of lead-iodide perovskites and propose novel lead-iodide peroskite absorbers with different cations at the center of the cuboctahedral cavity facilitating the tunning of the fundamental band gap [2].\\[4pt] [1] Filip, M. R. \& Giustino, F., http://arxiv.org/abs/1410.2029 (2014)\\[0pt] [2] Filip, M. R., Eperon, G., Snaith, H. J. \& Giustino, F., http://arxiv.org/abs/1409.6478 (2014)