Emission-tunable inorganic metal halide perovskite nanocrystals for passive Q-switched fiber laser

Metal halide perovskites have been considered as nonlinear optical materials owing to their favorable optics properties. Though CsPbBr₃ nanocrystals (NCs) are popularly emerging in optoelectronic devices, there has been little research on its nonlinear optical properties. In this work, emission-tunable CsPbBr₃ NCs were prepared by solution method at room temperature, and employed as saturable absorber (SA) to investigate its nonlinear optical properties. The cubic CsPbBr₃ NCs with 482 nm emission as SA showed the modulation depth of 3.7% and saturable strength of 0.91 MW cm⁻². CsPbBr₃ NCs have a maximum repetition rate of 840 kHz and a pulse width corresponding to 76 ns. The nonlinear optical properties of CsPbBr₃ NCs indicate their great potential applications in nonlinear optics and optical communication.