Solution-processed whispering-gallery-mode microsphere lasers based on colloidal CsPbBr3 perovskite nanocrystals

Perovskite nanocrystals (NCs) have emerged as attractive gain materials for solution-processed microlasers. Despite the recent surge of reports in this field, it is still challenging to develop low-cost perovskite NC-based microlasers with high performance. Herein, we demonstrate low-threshold, spectrally tunable lasing from ensembles of CsPbBr3 NCs deposited on silica microspheres. Multiple whispering-gallery-mode lasing is achieved from individual NC/microspheres with a low threshold of similar to 3.1 mu J cm(-2) and cavity quality factor of similar to 1193. Through time-resolved photoluminescence measurements, electron-hole plasma recombination is elucidated as the lasing mechanism. By tuning the microsphere diameter, the desirable single-mode lasing is successfully achieved. Remarkably, the CsPbBr3 NCs display durable room-temperature lasing under similar to 10(7) shots of pulsed laser excitation, substantially exceeding the stability of conventional colloidal NCs. These CsPbBr3 NC-based microlasers can be potentially useful in photonic applications.

Automated summary

This study demonstrates low-threshold, spectrally tunable lasing from CsPbBr3 nanocrystals deposited on silica microspheres. The lasing mechanism is elucidated as electron-hole plasma recombination through time-resolved photoluminescence measurements. The CsPbBr3 nanocrystals-based microlasers exhibit durable and stable room-temperature lasing.