Amplified spontaneous emission and lasing in perovskite nanocomposites

In this manuscript, a nickel acetate, Ni(AcO)
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, thin films incorporating MAPbBr
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(MA: methylammonium) semiconductor perovskite nanocrystals is proposed as a suitable media to generate amplified spontaneous emission (ASE) and random lasing (RL). These nanocomposites are conveniently spin-coated onto $\mathrm{SiO}_{2} / \mathrm{Si}$ substrates, forming active planar waveguides. The thicknesses of the films are properly adjusted to exhibit single-mode propagation at the emission wavelength of the nanocrystals (530 nm) and high strong-mater interaction of the mode with the active region. Under a nanosecond pulsed excitation, fabricated structures exhibit the generation of amplified spontaneous emission (ASE), which is outcoupled from the edge of the sample. Moreover, the waveguide also exhibits narrow lasing lines ($\lt200 \mathrm{pm}$) attributed to the generation of RL in the film. Optimal conditions are found to reduce the threshold down to $100 \mu \mathrm{J} / \mathrm{cm}^{2}$ in the best device. These results represent a significant advancement in the application of semiconductor perovskites for optical waveguiding technologies.