Indium-Tin-Oxide-Induced Tunability of Nonlinear Optical Absorption from CH₃NH₃PbBr₃ Nanostructure-Based Films: Implications for Nonlinear Optical Devices

Abstract

A series of CH3NH3PbBr3 (MAPbBr3) nanostructure-based films with various thicknesses on indium-tin-oxide (ITO)-covered substrates were fabricated by the spin-coating technique. The effects of ITO on the structure, surface morphology, and optical properties of MAPbBr3 thin films were investigated, respectively. Compared with monolayer MAPbBr3 thin films, the ITO buffer layer has the effect of improving the crystalline quality and preferential orientation of MAPbBr3 thin films, realizing the transition from reverse saturation absorption to saturation absorption. The tunability of nonlinear optical absorption was achieved by changing the thickness of the MAPbBr3 film. The maximum three-photon absorption coefficient of the monolayer MAPbBr3 film was 7.35 × 10–14 cm3/W2. The maximum third-order nonlinearity coefficient of MAPbBr3/ITO composite film was −1.04 × 10–5 cm/W. In addition, the finite-difference time-domain simulation results were in good agreement with the experimental results. These results indicate that the synthesized MAPbBr3 nanostructure-based films have potential applications in nonlinear optical devices.

Fabrication of High-Stability and -Sensitivity Perovskite Nanoparticles with a Core–Shell Structure for Surface-Enhanced Raman Scattering

“…It confirms that the in situ grown perovskite exhibits a highly preferred orientation single-phase cubic crystal structure with a lattice parameter of a = 5 . The diffraction peaks at 14.85, 21.15, 25.95, 30.10, 33.75, 45.85, 53.23, and 63.4° (2θ) correspond to the (100), (110), (111), (200), (210), (300), (222), and (400) crystal planes, respectively. , Studies have indicated that both the substrate material and the thickness of the spin-coated perovskite layer can affect the crystalline quality of the perovskite . According to Bragg’s law, specific interplanar spacing ( d ) will result in intense diffraction peaks at specific angles (θ).…”

“…44,45 Studies have indicated that both the substrate material and the thickness of the spin-coated perovskite layer can affect the crystalline quality of the perovskite. 46 According to Bragg's law, specific interplanar spacing (d) will result in intense diffraction peaks at specific angles (θ). The results indicated that there were four main diffraction peaks in Figure 2, corresponding to (100), ( 200), (300), and (400) crystal planes, respectively.…”