Third-order Nonlinear Optical Properties Of Cs₃Cu₂Br₅、CsMnBr₃ Perovskite Materials

The era of rapid development of laser technology makes the research of nonlinear optics increasingly perfect.Nonlinear optics is an indispensable branch of modern optics.It mainly explores the interaction between laser and matter.The development and research of nonlinear optical materials are also attracting increasing attention.Among them,perovskite materials becomes a new generation of semiconductor material due to excellent properties.Compared with traditional semiconductors,it attracts much attention due to its outstanding optical,electro-optical properties and easy synthesis methods.Perovskite materials can be prepared into various forms such as single crystals,thin films and nanocrystal.This allows metal perovskite materials to be applied in many fields such as solar cells,laser devices,light emitting diodes,optical sensors and so on.Studying the nonlinear optical properties of perovskite materials are prerequisite for exploring optical applications.Therefore,this thesis focuses on the synthesis and third order nonlinear optical properties of metal perovskite nanocrystal.Through the regulation and research of different metal material.The potential application ability of material is improved.Lead atoms in lead based halides are toxic.Poor stability,sensitive to humidity,light,and oxygen.Due to environmental and application considerations.The development of efficient,stable and non-toxic perovskite material is one of the focuses of optical materials research.Based on this,this thesis studied and prepared non-toxic and stable copper based Cs₃Cu₂Br₅and manganese based Cs Mn Br₃halides.And deeply explore its nonlinear optical performance.The content is as follows:Cs₃Cu₂Br₅nanometer materials are prepared by a simple and safe thermal injection method.The microstructure of the materials is tested using some characterization methods such as X-ray diffraction patterns,transmission electron microscopy,and photoluminescence testing.The characterization results show that Cs₃Cu₂Br₅nanometer materials are in the form of particles,with clear lattice stripes.Cs Mn Br₃nanometer materials exhibit the same shape as particles,but the difference is that the size and gap between particles are smaller,which increases the specific surface area of the material.The comparison of X-ray diffraction patterns showed that the two materials are successfully synthesized.The photoluminescence spectra show that Cs₃Cu₂Br₅and Cs Mn Br₃nanometer materials exhibit excellent luminescence properties at different wavelengths.PMMA can be used as a protective material for the optical properties of perovskite materials.Cs₃Cu₂Br₅、Cs Mn Br₃organic glass is synthesized by casting method.Preparation of organic glass with different content by adjusting the amount of material added.Then,the nonlinear optical properties of two different materials are tested using open and closed hole Z-scan techniques.The experimental data are analyzed through theoretical fitting.The subsequent analysis compares the effects of replacement metal ions on the nonlinear optical properties of perovskite materials.The results show that Cs₃Cu₂Br₅nanometer materials exhibit good reverse saturation absorption,Self-focusing effect and optical limiting properties.With the increase of material content,both nonlinear absorption and refractive properties will increase.Substitution of the metal ion Cs Mn Br₃enhances the reverse saturation absorption characteristics it exhibits.The synthesis and optical properties of Cs₃Cu₂Br₅and Cs Mn Br₃nanometer materials provide the new development direction for optics and optoelectronic device applications.