Solution-processed whispering-gallery-mode microsphere lasers based on colloidal CsPbBr₃perovskite nanocrystals.

Area of Science:

• Materials Science
• Optics and Photonics
• Nanotechnology

Background:

• Perovskite nanocrystals (NCs) are promising gain materials for solution-processed microlasers.
• Developing high-performance, low-cost perovskite NC-based microlasers remains a challenge.

Purpose of the Study:

• To demonstrate low-threshold, spectrally tunable lasing from CsPbBr₃NCs on silica microspheres.
• To investigate the lasing mechanism and stability of these perovskite NC microlasers.

Main Methods:

• Fabrication of CsPbBr₃NCs deposited on silica microspheres.
• Characterization using whispering-gallery-mode (WGM) lasing measurements.
• Time-resolved photoluminescence (TRPL) spectroscopy to determine the lasing mechanism.

Main Results:

• Achieved low-threshold (∼3.1 μJ cm^-2) WGM lasing with a cavity quality factor of ∼1193.
• Identified electron-hole plasma recombination as the lasing mechanism.
• Demonstrated spectrally tunable single-mode lasing by adjusting microsphere diameter.
• Observed durable room-temperature lasing stability exceeding 10⁷ laser shots.

Conclusions:

• CsPbBr₃NC-based microlasers offer a promising platform for low-cost, high-performance photonic devices.
• The demonstrated stability and tunability pave the way for practical applications in photonics.