Photoexcited Dynamics in Metal Halide Perovskites: From Relaxation Mechanisms to Applications

The past decade has witnessed a growing interest in metal halide perovskite (MHP) materials, driven by their promising applications in photovoltaics and optoelectronics. The further pursuit of improved performance and stability will rely on a clear understanding of the fundamental properties of these materials. In this Feature Article, we outline a representative set of studies detailing how ultrafast laser spectroscopy can be used to access the optoelectronic properties and photophysical mechanisms of halide perovskites. Beginning with a concise synopsis of MHP history and structural properties, the dynamic processes in MHPs related to the photovoltaic performance are discussed. A brief overview of the representative time-resolved optical spectroscopic techniques in MHP research is then provided. Afterward, the recent advances in exploring the carrier, lattice, and spatially resolved dynamic processes in halide perovskite are summarized. The last section is devoted to a range of applications using halide perovskites. Finally, our conclusions and outlook for the field with some predictions for future opportunities round off this Feature Article.