Transient Lasing Behaviors in MAPbBr3 Perovskite Microcavities

With tunable wavelength and low lasing threshold, organo-lead perovskites have become promising candidates as lasing sources, such as microlasers for optical integration. It is essential to understand their lasing mechanism and control the lasing behavior at an ultrafast time scale. In this work, we prepared a series of square MAPbBr3 single-crystalline microcavities with/without Bragg reflectors. The transient lasing mode behavior was found to be size-dependent, i.e., a stronger red shift and a slower decay occurred in larger microplates. This inevitable transient red shift reduces the mode quality of perovskite microlasers, which can be attributed to the electron–hole plasma decay at a high excitation density. For optimization, distributed Bragg reflectors (DBRs) were applied with successful suppression of the transient mode shift. This work provides systematic insight to understand the transient behaviors of perovskite lasing microcavities, which would guide the design of perovskite-based light sources for optical communication and integration.