摘要
Due to the tunable bandgaps, high quantum efficiency, and long carrier diffusion length, perovskites have attracted significant attention as active materials for solar cells, nanoscale lasers, photodetectors, and light-emitting diodes. Herein, laser-induced dual-wavelength emissions from the CsPbBr3xI3(1-x) perovskite alloy microcrystals are reported. Under a 375 nm laser illumination, the micro-photoluminescence (PL) emission spectra of these microcrystals exhibit two emission bands at 570 and 690 nm with gradually increased and decreased PL intensity, respectively. Moreover, the time-dependent emission wavelength of the two emission bands almost has no changes, while the PL intensity of both emission bands shows periodic fluctuations with the on-off switching of excitation light. This dual-wavelength emission phenomenon suggests that phase segregation occurs in these perovskite microcrystals during laser illumination. These results would provide valuable design guidelines for perovskites-based tunable nanophotonic devices and multi-color displays.