Refractive Index Dispersion of Organic–Inorganic Hybrid Halide Perovskite CH₃NH₃PbX₃ (X═Cl, Br, I) Single Crystals

Abstract

Abstract Optical dispersion properties are indispensable in the thorough design of modern perovskite‐based photonics devices. Based on inverse temperature crystallization (ITC) method, here, CH 3 NH 3 PbX 3 (CH 3 NH 3 ═MA, X═Cl, Br, I) bulk single crystals are grown from precursor solution. X‐ray patterns indicate that the perovskite crystals have good crystallinity. MAPbCl 3 , MAPbBr 3 , and MAPbI 3 crystals are transparent above 427, 574, and 823 nm, respectively. Refractive indices of MAPbX 3 crystals are measured with different wavelength at 24 °C and reduced dramatically with the wavelength increase. Sellmeier dispersion equation fitted by least squares can be used to calculate the refractive index above the absorption edges. Refractive indices rank in the order of MAPbI 3 > MAPbBr 3 > MAPbCl 3 at the same wavelength. The halogen elements have great influence on refractive indices. These results play a vital role in studying MAPbX 3 nonlinear optical properties as well as in further designing photoelectric devices.