Laser patterning of large-scale perovskite single-crystal-based arrays for single-mode laser displays

Lead halide perovskites have attracted considerable attention as potential candidates for high-performance nano/microlasers, owing to their outstanding optical properties. However, the further development of perovskite microlaser arrays (especially based on polycrystalline thin films) produced by the conventional processing techniques is hindered by the chemical instability and surface roughness of the perovskite structures. Herein, we demonstrate a laser patterning of large-scale, highly crystalline perovskite single-crystal films to fabricate reproducible perovskite single-crystal-based microlaser arrays. Perovskite thin films were directly ablated by femtosecond-laser in multiple low-power cycles at a minimum machining line width of approximately 300 nm to realize high-precision, chemically clean, and repeatable fabrication of microdisk arrays. The surface impurities generated during the process can be washed away to avoid external optical loss due to the robustness of the single-crystal film. Moreover, the high-quality, large-sized perovskite single-crystal films can significantly improve the quality of microcavities, thereby realizing a perovskite microdisk laser with narrow linewidth (0.09 nm) and low threshold (5.1 μJ/cm2). Benefiting from the novel laser patterning method and the large-sized perovskite single-crystal films, a high power and high color purity laser display with single-mode microlasers as pixels was successfully fabricated. Thus, this study may offer a potential platform for mass-scale and reproducible fabrication of microlaser arrays, and further facilitate the development of highly integrated applications based on perovskite materials.