Investigation on Lasing Behaviors from Morphology-Controlled Organic-Inorganic Halide Perovskite Waveguide

【摘要】：Low-temperature solution-processed tri-halide perovskite have been successfully used as light-absorbers and light-sources in many researches. The crystallinity and proper morphology are important factors for perovskites-based lasing devices. Here, we report a tow-step solvent-engineering process that comprising the N, N-dimethylmethanamide and dimethylsulfoxide as the binary solvent to fabricate a CH_3NH_3 Pb I_3 perovskite thin film based on the Pb I_2(solvent) complex layer. The use of a mixed solvent of DMF and DMSO followed by dip-coating leads to a controllable converting extent and uniform perovskite layers, and enables the ultra-stable amplified spontaneous emission at low thresholds. The optimized binary solvent based perovskite thin films showed threshold of 1.04 μJ/pulse and full width of half maximum of 8.16 nm at 780 nm at room temperature, which are much better than that of perovskite films based on the non-solvent processed Pb I_2 films. The phase transition at 160 K was also observed via PL spectra and absorption spectra shift. Our work proved that the binary solvent-engineering can control and optimize the crystallinity and morphology of the CH_3NH_3 PbI_3 perovskite thin films and provided an effective strategy for fabricating a more efficient and cost-effective inorganic-organic hybrid light-pumped, even electric-pumped, amplified spontaneous emission lasing device.