Bimolecular and Auger Recombination in Phase-Stable Perovskite Thin Films from Cryogenic to Room Temperature and Their Effect on the Amplified Spontaneous Emission Threshold

Recently, continuous-wave (CW) lasing was demonstrated at room temperature in quasi-2D perovskites. For 3D films, CW lasing at room temperature remains challenging. Issues hampering 3D materials include the temperature dependence of the (a) distribution of carrier energies, (b) buildup of photoinduced nonradiative channels, and (c) rates of bimolecular versus Auger recombination. We study the latter in a phase-stable 3D perovskite using high-index substrates to completely suppress amplified spontaneous emission (ASE). The bimolecular recombination coefficient decreases from 80 to 290 K (from (6.4 to 1.1) x 10(-10) cm(-3) s(-1)), whereas the Auger coefficient stays constant at 3 x 10(-29) cm(-6) s(-1). Above 250 K, the Auger rate exceeds the bimolecular rate at carrier densities corresponding to the ASE threshold. At lower temperatures, the decrease in the bimolecular rate coefficient with increasing temperature and the fraction of photoluminescence in the ASE band determine the temperature dependence of the ASE threshold.

Automated summary

This study demonstrates room temperature continuous-wave lasing in quasi-2D perovskites, while highlighting the challenges in achieving the same in 3D films. By investigating bimolecular and Auger recombination rates in a phase-stable 3D perovskite, with the help of high-index substrates, the researchers observed a decrease in the bimolecular recombination coefficient with increasing temperature, influencing the temperature dependence of ASE threshold.