Continuous‐Wave Vertical Cavity Surface‐Emitting Lasers based on Single Crystalline Lead Halide Perovskites

Abstract Lead halide perovskites are intriguing semiconductors for lasers due to high quantum yield, tunable bandgaps, and facile solution‐process ability. However, limited by the weak optical confinement, continuous‐wave (CW) pumped lasing, as one prerequisite for the electrically pumped lasing, is still challenging in bare lead halide perovskites without high‐quality factor ( Q ) artificial optical cavity. Herein, the lasing emission in methylammonium lead tribromide (MAPbBr 3 ) incorporated with a vertical microcavity under continuous pumping at 80 K is reported. The single‐crystalline MAPbBr 3 perovskite nanoplates are fabricated by the two‐step solution method. The MAPbBr 3 ‐based vertical cavity surface‐emitting laser (VCSEL) presents a low threshold of 55.2 W cm −2 and a high Q ‐factor of 1140 at low temperature. The low threshold lasing emission can be attributed to strong optical confinement in the high‐ Q cavity and great photoluminescence enhancement at 80 K, which is induced by a transition from tetragonal to orthorhombic phase, demonstrated by in situ temperature Raman spectroscopy. These findings envisage the prospective applications of single‐crystalline metal halide perovskites in practicable laser devices.