Internal quantum efficiency of radiation in a bulk CH3NH3PbBr3 perovskite crystal quantified by using the omnidirectional photoluminescence spectroscopy

Abstract

The internal quantum efficiency (IQE) of radiation for bulk CH3NH3PbBr3 crystals was quantified by using omnidirectional photoluminescence spectroscopy. The angle-resolved photoluminescence revealed that the emission with photon energies higher than the absorption-edge shows a Lambertian distribution and that the light extraction efficiency is determined by the escaping cone. The IQE value strongly depends on the photo-excitation density (P), and a CH3NH3PbBr3 crystal fabricated under the methylammonium-rich conditions gave the maximum IQE of 62.5% under P = 28 W/cm2. A further increase in P gave rise to the decrease in IQE due to the Auger effects.