Investigation On Synthesis And Photoelectric Magnetic Properties Of Organic-inorganic Perovskite

In recent years,organic-inorganic perovskite has been widely used in optical devices for its excellent photoelectric properties.However,due to the limitation of the technology,the preparation of large-area perovskite films with uniform mass is still a research difficulty.Therefore,in this paper,the optical response characteristics of organic perovskite materials are systematically analyzed,and organic perovskite terahertz metamaterials are prepared to achieve optical dynamic tuning.The research contents are as follows:1.The organic-inorganic hybrid perovskite was prepared by spin coating chemical vapor deposition method.The influence of the preparation method of precursor substrate on the sample morphology was studied systematically.The samples were characterized by atomic force microscope,Raman spectrum,photoluminescence spectrum,UV absorption spectrum and other methods.The results show that a large area,uniform and high quality organic-inorganic hybrid perovskite film is obtained.2.The ultrafast optical response of organic-inorganic hybrid perovskite samples was studied by 400 nm optical pumping broadband optical detection and 500 nm optical pumping terahertz detection.The results show that the bleaching signals are generated at 738 nm and 496 nm under broadband light detection,which are caused by surface valence band and deep valence band to conduction band transitions respectively;under terahertz detection,comparing the ultrafast response characteristics of lead iodide,we know that the absorption at 496 nm is mostly from the residual lead iodide crystal.The mechanism of exciton generation and recombination after optical pumping is obtained by analyzing the signal decay process under two kinds of testing systems: the highspeed recombination stage is mainly caused by single molecule recombination and bimolecular recombination,while the slow speed recombination stage is mainly caused by Auger recombination.3.Using the software to design the unit structure of the metamaterial,introducing the complex permittivity simulation of the silicon,it is found that the structure produces LC resonance at 0.408 thz,and realizes dynamic tuning by changing the conductivity of the surface material;according to the simulation results,the gold film metamaterial is prepared on the high resistance silicon substrate,and a layer of organic perovskite film is spin coated on the substrate,which is carried out by adjusting the pump light power The maximum modulation depth is 30%,which is basically consistent with the simulation results.