Two-dimensional (2D) layered lead halide perovskites with large exciton binding energies, efficient radiative recombination, and outstanding environmental stability are regarded as supreme candidates for realizing highly compact and ultralow threshold lasers. However, continuous-wave (CW) pumped lasing of 2D lead halide perovskites, as the precondition for the electrically pumped lasing, is still challenging. Here, we tackled this challenge by demonstrating lasing emission in phenylethylammonium lead iodide [(PEA)₂PbI₄] embedded in a vertical microcavity under continuous pumping at room temperature. The millimeter-sized (PEA)₂PbI₄ single crystal was obtained from a two-step seed-growth method, showing high crystallization, excellent thermal stability, and outstanding optical properties. We used the exfoliated (PEA)₂PbI₄ thin flake as the gain medium to construct a vertical-cavity surface-emitting laser (VCSEL), showing robust single-mode CW lasing operation with an ultra-low threshold of 5.7 W cm⁻² at room temperature, attributed to strong optical confinement in the high-Q cavity. Our findings provide a strategy to design and fabricate solution-based 2D perovskite VCSELs and mark a significant step toward the next-generation of coherent light sources.

中文翻译：

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基于二维层状有机-无机杂化钙钛矿的室温连续波垂直腔面发射激光器

具有大激子结合能、高效辐射复合和出色环境稳定性的二维 (2D) 层状卤化铅钙钛矿被认为是实现高度紧凑和超低阈值激光器的最佳候选材料。然而，作为电泵激激光的先决条件，二维卤化铅钙钛矿的连续波 (CW) 泵浦激光仍然具有挑战性。在这里，我们通过展示在室温下连续泵送下嵌入垂直微腔中的苯乙基碘化铅 [(PEA) ₂ PbI ₄ ] 中的激光发射来解决这一挑战。毫米级 (PEA) ₂ PbI ₄单晶是通过两步种子生长法获得的，具有高结晶度、优异的热稳定性和出色的光学性能。我们使用剥离的 (PEA) ₂ PbI ₄薄片作为增益介质来构建垂直腔面发射激光器 (VCSEL)，显示出稳健的单模 CW 激光操作，具有 5.7 W cm ^-2的超低阈值在室温下，归因于高 Q 腔中的强光限制。我们的研究结果提供了一种设计和制造基于解决方案的 2D 钙钛矿 VCSEL 的策略，并标志着朝着下一代相干光源迈出的重要一步。