Paving the way for solution- processable perovskite lasers

Trihalide perovskites have been studied quite extensively as light‐harvesting media in photovoltaic devices and have shown a peculiar blend of optoelectronic properties, particularly remarkable carrier mobilities, diffusion lengths comparable to those of inorganic semiconductors and band gap tuneability. Only limited research effort, though, has been devoted so far to leveraging such properties for light emission, and many related processes remain unclear. Here, we identify organic‐inorganic metal halide perovskites as promising candidates for replacing a variety of raw materials at risk of supply shortage, currently used in manufacturing gain media for commercial lasers. We investigate the dynamics of light emission by transient photoluminescence spectroscopy and on the grounds of our findings we identify the challenges ahead on the way to engineering perovskite‐based lasers. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)