Robust Cesium Lead Halide Perovskite Microcubes for Frequency Upconversion Lasing

Halide perovskite nanomaterials have recently attracted a lot of attention in the nanoscale laser research field, especially two-photon pumped lasing in halide perovskite nanomaterials has been considered as an ideal alternative strategy to achieve frequency upconversion. However, the poor stability of current organic-inorganic lead halide perovskite materials hinder their further practical applications. Herein, facile solution-processed cesium lead halide perovskite CsPbX3 (X = Br, I, or Cl) microcubes with low-threshold lasing, high quality, enhanced stability, and excellent wavelength tunability are reported. These as-prepared CsPbX3 microcubes display excellent structure stability under ambient conditions for several months and they are found to be more robust than their organic-inorganic counterparts. The smooth end facets and wavelength-comparable dimensions make these microcubes promising for high-quality laser cavities in three dimensions. Fabry-Perot lasing is demonstrated in CsPbX3 microcubes, the process of which is investigated by dynamic emission. In addition, tunable amplified spontaneous emission is achieved with low threshold under both one- and two-photon excitation, which can maintain a stable emission for over 10 hours under continuous intense laser shots in ambient atmosphere. The findings suggest that solution-processed all-inorganic perovskite microcubes can be used as excellent gain medium for frequency upconversion lasers, which would offer a new platform for nonlinear photoelectric devices.