Size-controlled Patterning of Single-crystalline Perovskites Arrays toward Tunable High-performance Microlaser

Single-crystalline halide perovskites with regular morphology are of great significance for laser applications because they can be used to fabricate a natural whispering-gallery-mode resonator. Although enormous efforts have been put to synthesize single-crystalline perovskites, controlling the lateral size and thickness of the crystal, particularly at the nanoscale, is still challenging. Here, we report a facile and high-throughput strategy to selectively one-step create micro/nanoscale size-controlled all-inorganic perovskite single-crystal arrays by surface-tension-confined evaporative assembly. Our method can be used to easily tune the single crystal size and selectively position the single crystal, with versatility in fabricating perovskite single-crystal arrays in wafer scale. When the patterned size increases from 2 to 25 μm, the width of the CsPbClBr2 perovskite microplates increased from 150 nm to 4.2 μm. Fixing the width of the microplates at 1.6 μm, with the increase of the sliding speed from 5...