Superior nonlinear optical performance of CsPbBr₃ all-inorganic metal halide perovskite nano-crystals embedded Ge₂S₃ chalcogenide glass

In this work, we synthesized a novel optical functional nanocomposite material by incorporating all-inorganic metal halide perovskite (MHP, CsPbBr₃) nano-crystals to Ge₂S₃ chalcogenide glass (ChG), and discovered their superior nonlinear optical performance, which is as good as organic-inorganic hybrid MHPs. This all-inorganic MHP-ChG nanocomposite has tunable nonlinear refractive index (<i>n</i>₂) and two-photon absorption coefficient (<i>β</i>_2PA) via crystallinity of the MHP crystals, as well as exceptional optical limiting performance, with optical limiting threshold (OLT) values in the near-infrared wavelengths ranging from tens to hundreds of μJ/cm², which greatly outperforms the OLT reported for most existing optical limiting materials. This renders the present MHP-ChG nanocomposites highly promising for applications in laser protection based on optical limiting.