Fluorescence Temperature Properties Of Eu³⁺: YVO₄

As one of the seven basic physic quantities in International System of Units,temperature is closely related with almost all fields in science and technology aswell as productions. Reseant years, a new optical temperature sensing method basedon fluorescence temperature effect of rare-ions has received considerable attention.The method has a lot of advantages such as uncontact and high measurementaccuracy. It can also work in strong electric, mangnetic and other complexenvironments and easy to measure temperature distribution. But there are still someproblems, fluorescence quenchs seriously in high temperature. Up-conversionfluorescence pumped by a monochromatic light source is inefficiency for energytransfer, then influence temperature sensitivity. Based on the above considerations,this paper reaserach the fluorescence temperature properties of Eu3+ions on the onthe sample of Eu3+: YVO4.In this paper, by derivating fluorescence intensity ratio formula can know thatthe most important facter to improve the accuracy of Eu3+temperature measurementis to enhance the fluorescence intensity of5D1�'7F1transition. The paper improvesfluorescence intensity by optimizing the doping concentration of Eu3+and dopingLi+. Experiments confirme that the doping of Li+into sample Eu3+: YVO4has noinfluence to the sample’s excitation spectrum and fluorescence spectra.In roomtemperature, Eu3+:YVO4samples has a broadband ultraviolet absorption between220-350nm, that proved to be the V-O charge transfer band of the ground.We use405nm laser to pump the sample of Eu0.1Y0.9VO4, get the thermalcoupling energy level width by fitting fluorescence intensity ratio of5D71�'F1transition and5D70�'F1transition. These experimental results are consistent with theother researchers’ results. We measured all the Eu3+transition fluorescence, madetwo of these transitions’ fluorescence intensity ratio, we get the followingconclusion: not only the fluorescence intensity ratio of5D771�'F1and5D0�'F1transition can be used in measuring temperature, but also the fluorescence intensityratio of5D5755751�'7F1andD0�'F2,D0�'7F3,D0�'7F4;5D51�'7F2andD0�'F1、D0�'7F752、5D0�'F3、D0�'7F4can do. Fluorescence intensity of Eu0.1Y0.9VO4excited by405nm laser constantly increases with the temperature rising from323K to773K.That provides an excitation source and related sample to measure temperature inrelative high temperature range. The paper explored the changes of excitation spectra of Eu0.1Y0.9VO4in thetemperature range of323-773K. The sample’s V-O charge band has some variation.The band’s peak value is increasing and peak position shift to long wavelength asthe temperature rising. That provides a new fluorescence temperature sensingexcitation source, a broadband spectral model excitation source. In this paper, wefind a broadband spectral and confirm its possible in measuring temperature. In773K, the relative sensitivity of sample Eu0.1Y0.9VO4pumped by broadband source is0.28%/K. Based on the above study, the paper found a suitable sample matrix whichis efficient in down-conversion fluorescence thermometry to design a new type ofbroadband spectrum excited fluorescence thermometry method. The paperconfirmed that the broadband spectrum fluorescence thermometry can be achieved.