Highly Controllable Lasing Actions in Lead Halide Perovskite–Si3N4 Hybrid Micro‐Resonators

Lead halide perovskite (MAPbX3) nanosheets are promising materials for optoelectronic devices. However, as the as-grown perovskite nanosheets typically have random sizes, positions, and alignments, their device performances are hard to be controlled and repeated, significantly hindering the practical applications in nanophotonics. Herein, a novel approach to realize highly controllable lasing actions in MAPbX3 nanosheets is demonstrated. By hybridizing the perovskite with an Si3N4 wafer, it is shown that the cavity shape and the internal lasing actions are precisely controllable via the patterns in Si3N4 wafer, which is pre-defined with mature CMOS technique and will not spoil the exceptional gain of perovskite nanosheet. Consequently, whispering gallery mode (WGM) micro-lasers with well-controlled mode numbers, mode spacing, repeatability, directionalities, and even internal angular momentum are experimentally realized. In addition, by constructing coupled micro-structures, the proximity effects between WGM lasers are also explored. This research provides a substrate-control mechanism to precisely define and control MAPbX(3) perovskite micro-lasers.