Etude et caractérisations spectroscopiques des verres fluores ZBA dopés par les différents éléments de terresrares l’ER, l’HO et l’EU

Abstract

Glasses based on zirconium fluoride (ZrF4) are the first fluoride glasses discovered by the brothers

Poulain in 1975. Since this discovery, a real competition has been launched for a judicious choice of

the chemical composition in order to synthesize more thermally stable glasses. Indeed, several

studies have been conducted on the ability of some fluorides verification and the effect of all

components on the properties of glass. Especially, the rare earth elements used as dopants to

improve luminescent properties of the glass.

We carried out a systematic study about the effect of the matrix ZBA (ZrF4-BaF2-AlF3) on the

spectroscopic properties of different rare earth element (Er, Eu and Ho).

The UV-Visible and IR absorption spectra (or transmission) were recorded for the different

samples. And show a glasses transparence up to the wavelength. This limit is known as the cutoff

multi-phonons, it is an intrinsic characteristic of the ZBA matrix. The transmission curves samples

depict a several peaks due to corresponding absorption of rare earth ions.

Several emission spectra were performed for two different excitation wavelengths of(532 and

808nm).Based on these spectra, we have observed the Up-conversion phenomenon, giving more

energy emissions that photons absorbed. This phenomenon is particularly observed in the Er case

and is completely absent in Eu and Ho cases.

It is connected to the two photons absorption mechanism which depends on excited states energy

and their lifetimes.