Performance Of Yb-Tm-Gd Co-doped Nanocrystalline Oriented Deep Ultraviolet Laser

Rare earth ions have an unparalleled position in the field of up-conversion luminescence due to their unique electronic layer structure.However,due to factors such as concentration quenching and unnecessary energy loss,the up-conversion luminous efficiency is low.This problem limits the further development of rare earth ions.In the field of upconversion luminescence,the research scope is more in the near-infrared to visible light band,and there are few reports in the deep ultraviolet band.Therefore,deep ultraviolet upconversion luminescence based on rare-earth ion doping has great research significance.Due to the rotational symmetry of the traditional optical resonator,the emitted light is isotropic.In order to solve this problem,a snail-shaped deformable cavity is selected to obtain a directional emitting laser.By combining chemical preparation and micro-nano preparation,rare earth ion nanocrystals and snail-shaped deformable cavity are combined to prepare an on-chip micro deep ultraviolet laser that can be integrated,and finally a directional deep ultraviolet laser is obtained.In this paper,the co-precipitation method is used as a chemical preparation method to prepare Li Yb F₄:Tm/Gd@Li Yb F₄@Li Lu F₄nanocrystals with a core-shell-shell structure by first synthesizing the core structure and then gradually synthesizing the shell structure.The prepared nanocrystalline samples were characterized by XRD structure and TEM morphology.The characterization results showed that the prepared nanocrystalline samples had uniform size distribution,good crystallinity and regular morphology.In addition,the deformed cavity was prepared by standard semiconductor processing technology and laser reflow method.At the same time,SEM characterization and quality factor test of the deformed cavity were performed.The results showed that the prepared deformed cavity had a complete structure,standard size,and a high Q value.This paper also studied in detail the fluorescence performance of the prepared up-conversion nanocrystals.The luminescence peak of the sample was analyzed through the angle of energy level.The deep ultraviolet up-conversion luminescence at 252 nm was realized when pumped with 980 nm continuous light,and explored The influence of sample dilution factor on the luminous intensity is discussed.The980 nm pulsed light was used as the pump light source to study the laser performance of the nanocrystals,and the relationship between the luminous intensity and the luminescence spectrum and the detection angle under different powers was studied.The final result shows that the luminous intensity of the sample increases first and then decreases with the dilution factor.In the random laser test process,it was also proved that the sample produced random laser,which indicated that the ⁶D_9/2energy level of Gd³⁺ion had a population inversion to realize laser emission,and the doping system completed the energy transfer.This article tests and analyzes the light-emitting directionality of the on-chip micro-laser.Obvious directivity is observed in the graph of the relationship between laser intensity and angle obtained by the test.The above results can show that it is feasible to use the combination of rare earth ions and the deforming cavity to prepare a directed deep ultraviolet laser.The successful combination of chemical technology and micro-nano technology also provides new ideas for the development of traditional chemistry.The acquisition of directional deep ultraviolet lasers has further expanded the application range of deep ultraviolet lasers.