Temperature Dependence Fluorescence And Laser Properties Of CsPbBr₃ Microplates

Metal halide perovskites are considered as excellent gain media for lasing applications due to their high optical absorption coefficient,high charge carrier mobility,long carrier diffusion length and so on.Therefore,microcavities based on metal halide perovskite materials have broad application prospects in the field of integrated optoelectronic chips.A systematic study of temperature-dependent spontaneous emission and lasing properties of CsPbBr₃ microplates which synthesized by chemical vapor deposition(CVD)is presented.The main results are as follows:Firstly,the high quality CsPbBr₃ microplates were synthesized by chemical vapor deposition equipment based on quartz tube furnace.By adjusting the carrier gas flow rate and the reaction pressure,the CsPbBr₃ microcavity structures were synthesized which have good geometry and high crystallization quality.It can produce lasers.Secondly,the lasing mechanism of CsPbBr₃ microplates at room temperature was determined by the pump fluene dependent lasing spectra.By the fact that the lasing peak position does not shift with the increase of pump fluence,it is determined that the exciton is the main factor that dominates the room temperature laser of the CsPbBr₃microplates.Finally,by the temperature-dependent spontaneous emission and lasing spectra of the CsPbBr₃ microplates,it is determined that lattice thermal expansion and exciton-phonon interaction play an important role of the photoexcitation process below 353 K.By the corresponding temperature dependent spontaneous emission spectra fitting we found that the photoexcitation process is dominated by lattice thermal expansion when temperature below 230 K and exciton-phonon interaction when temperature above 230K.In a word,we investigate the temperature-dependent fluorescence and laser properties of CsPbBr₃ microplates in detail by a self-built spectral testing system.These results will facilitate our understanding of the process of exciton-dominated photophysics based on perovskite microcavity structures.It will help to fabricate low threshold laser devices for integrated optoelectronic chip applications.