Highly Controllable Lasing Actions in Lead Halide Perovskite–Si ₃ N ₄ 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 Si ₃ N ₄ wafer, it is shown that the cavity shape and the internal lasing actions are precisely controllable via the patterns in Si ₃ N ₄ 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.