Bulged CH3NH3PbBr3 Microwires for Single-Mode Lasing

Herein, the lasing action of fabricated bulged CH₃NH₃PbBr₃ microwires is demonstrated with features of a low threshold, narrow linewidth, single-mode operation, and high intensity. Benefiting from the bulged end facets, the CH₃NH₃PbBr₃ microwires are feasible for constructing a high-brightness, whispering-gallery-mode(WGM)-type, and single-mode laser while suppressing Fabry–Pérot-type multi-mode lasing. Numerical simulation unveils that the bulged end facets result in the significantly reduced reflectivity of fundamental waveguided modes. The obtained microlasers require neither complex structures (such as distributed Bragg reflector) nor careful pumping adjustment, suggesting the practical feasibility of a higher single-mode lasing intensity than conventional WGM perovskite microlasers. The results provide new routes to realize high-performance perovskite microlasers and their potential application in sensing refractive index.