| In recent years,with the development of device miniaturization and optical integration,it is currently a research topic to explore new magneto-optical materials with large dimensions,high Verdet constant,simple growth methods and high optical quality.Organic-inorganic perovskite materials have received a large amount of attention in magneto-optical and other research due to their good opt-magnetic properties such as solution processability,high absorption coefficients,long carrier lifetimes,spin-polarized emission,photo-induced magnetization and long spin lifetimes.To investigate the possibility of using perovskite single crystals in Faraday rotators,in this work,the optimized inverse temperature crystallization（ITC）method has been successfully used to fabricate CH3NH3Pb X3（X=Cl,Br）（CH3NH3+=MA+）single crystals.The structure and properties of MAPb X3（X=Cl,Br）are characterized.And the Faraday rotation system is set up to explore the rotational properties of MAPb X3（X=Cl,Br）single crystals.Finally,the applications prospects of MAPb X3（X=Cl,Br）-based single crystals in opto-isolators are discussed.The specific work is as follows:（1）The conventional ITC method is optimized to control the influence of temperature and external environment on the single crystals to synthesize high quality and large size perovskite single crystals.MAPb X3（X=Cl,Br）prepared by the optimized ITC method is a cubic single crystal system.The grown single crystals are high purity,no impurities,large size and high crystal quality.（2）The Faraday rotation system is built to investigate the magneto-optical effect of MAPb X3（X=Cl,Br）crystal samples under the magnetic field up to 1 T.And the influence of the Verdet constant of perovskite single crystals are analyzed based on the Becquerel formula.It can be found that the MAPb Cl3 single crystal has a Verdet constant of 411 rad/（T?m）at435 nm and MAPb Br3 single crystal has a Verdet constant of 418 rad/（T?m）at 470 nm.Compared with the industry-standard terbium gallium garnet（TGG）material,the Verdet constant of MAPb Cl3 single crystal at 435 nm is approximately 1.5 times higher.By altering the halogen,Faraday rotation of perovskite single crystal can be extended to the UV-visible part of the spectrum.（3）The prospect of using MAPb X3（X=Cl,Br）single crystals on optical isolators is investigated by experimental calculations of isolation transparency and transient thermal response simulations.Taking MAPb Cl3 as an example,it is calculated that an optical isolator made from MAPb Cl3 single crystal can achieve 90%isolator transparency at wavelengths of435 nm and 450 nm with a 0.32 T magnetic field.In addition,the transient thermal response of MAPb Cl3 single crystal is simulated in context of device optimization by combining parameters such as thermal conductivity,density and specific heat.It can be found that MAPb Cl3 single crystal has low temperature dependence and good thermal diffusion characteristics.The research work indicates that the perovskite single crystals have good magneto-optical properties,while by changing the halogen structure of the material,the working wavelength of the material can be controlled.A new direction is provided for the practical application of electro-optic isolation devices based on perovskite single crystals. |
