Optically pumped lasing of segregated quasi-2D perovskite microcrystals in vertical microcavity at room temperature

Quasi-2D Ruddlesden-Popper perovskites possess a tailorable quantum well structure and outstanding optical properties. Herein, we study their diverse phase-separation phenomena and the resulting microcrystals (∼1 μm), which have evidently enhanced photoluminescence. Lasing based on these microcrystals in a vertical single-mode optical microcavity has also been achieved, featuring a low threshold of ∼500.0 μJ/cm² pumped by a nanosecond pulsed laser (355 nm, pulse width 8 ns, 1 kHz). This work makes the quasi-2D perovskite microcrystals potential candidates to be gain materials for continuous wave lasing.