Study On Nonlinear Photoluminescence Of Platinum Diselenide Two Dimensional Materials Based On Fabry-Perot Cavity

Two-dimensional materials refer to materials in which electrons can only move freely on two scales.Due to its unique properties,two-dimensional materials have attracted wide attention and developed rapidly in recent years.Transitional metal disulfides(TMDs)is a large branch of two-dimensional materials,including Mo S₂,WS₂,WSe₂,etc.While PtSe₂ is a recently-emerged new type of TMD material,with many unique physical properties,suh as good air stability,large refractive index and high electron mobility.This paper mainly studies the nonlinear photoluminescence of PtSe₂ and explore its application.The main innovation points and research contents of this paper are as follows:1.The F-P optical resonator of Si-SiO₂-PtSe₂ is prepared by chemical vapor deposition method.The position of the resonant wavelength can be changed by tuning the thickness of SiO₂ layer.By controlling the excitation wavelength of femtosecond laser,the luminescence of PtSe₂ can be excited with different intensity by changing the power of femtosecond laser,and the mechanism of photoluminescence of PtSe₂ can be obtained.2.For the prepared PtSe₂ sample,the luminescence enhancement of PtSe₂ by femtosecond laser excitation at the resonant wavelength can be obtained by changing the excitation wavelength of the femtosecond laser.According to different wavelengths of femtosecond laser excitation of the sample,we can get the luminescence intensity and luminescence image excited at different wavelengths.By comparing with the microscope image obtained under white light irradiation,we can get the difference of linear optical properties and nonlinear optical properties of PtSe₂.3.The thickness of PtSe₂ layer can be controlled by the use of 532 nm laser for sample processing.Thus we can explore the luminescence characteristics of F-P optical resonator composed of PtSe₂ layers with different thickness.We obtained the dependent relationship between the nonlinear photoluminescence characteristics of PtSe₂ and its thickness through experiments.When the thickness decreases monotonously,the luminescence intensity increases first and then decreases,which provides a certain possibility for further improving the luminescence response of PtSe₂.