Low threshold amplified spontaneous emission in ultrastable CsPbBr3-TS-1 nanocomposite films under two-photon excitation

Abstract

Perovskite nanomaterials have attracted significant attention in the field of nanoscale laser field, however, poor environmental stability is the biggest challenge that restricts their applications. In this study, an in situ synthesis method was used to encapsulate CsPbBr3 nanocrystals (NCs) in titanium silicalite molecular sieve (TS-1). Owing to the hollow structure and the hydrophobicity of the TS-1, the hydro and thermal stabilities of the perovskite NCs were significantly improved. Using AB glue, we prepared thin films using a one-step spin coating method, and synthesized highly compact and smooth CsPbBr3 nanocomposite thin films. Amplified spontaneous emission (ASE) was achieved with a low-threshold under two-photon excitation at room temperature, and a stable emission under continuous intense laser shots in an ambient atmosphere was maintained. The influence of the perovskite concentration and calcination temperature on the ASE threshold was also investigated. This study will significantly broaden the application of perovskite nanocrystals in practical nonlinear optical devices.