Investigation on binding energy and reduced effective mass of exciton in organic-inorganic hybrid lead perovskite films by a pure optical method

The exciton binding energy and its reduced effective mass in hybrid lead perovskite, which play a key role in the process of excitons forming, largely determine the excellent optical properties of the perovskite materials and hence, the device performance. We introduce the systematic measurements on these two parameters of the organic-inorganic hybrid perovskite films of (MA/FA)Pb(Br/I)(3) by a unique temperature and density-resolved optical spectroscopic method. The method is simple and straightforward, since it directly observes the exciton ionization and recombination. Our results describe the fundamental photoelectric properties for understanding the excellent performance of the perovskite materials. (C) 2019 Optical Society of America