G.R.  Barrera, A.L.F.  Novais, A.S.  Almeida, L.F.  Souza, C.M.  Abreu, F.T.  Galindo, F.C.L.  Ferreira, N.  Souza, 
    Luminescence and Lifetime of CaO-Al<sub>2</sub>O<sub>3</sub>-B<sub>2</sub>O<sub>3</sub> : Yb<sup>3+</sup> and CaO-Al<sub>2</sub>O<sub>3</sub>-B<sub>2</sub>O<sub>3</sub>: Ce<sup>3+</sup>
Rare-Earth-Doped Borate Glasses,
    Journal of Engineering and Applied Sciences,
    Volume 15,Issue 4,
    2020,
    Pages 932-937,
    ISSN 1816-949x,
    jeasci.2020.932.937,
    (https://makhillpublications.co/view-article.php?doi=jeasci.2020.932.937)
    Abstract: This recherche aimed to investigate the characteristics related to the photo luminescence properties
of borate glasses CaO-Al<sub>2</sub>O<sub>3</sub>-B<sub>2</sub>O<sub>3</sub> doped with 1.0% of Yb<sup>3+</sup> and Ce<sup>3+</sup>. These glasses were prepared by using
a melt-quenching technique and characterized through X-Ray Diffraction (XRD) and Fourier-transform infrared
spectroscopy and photo luminescence and decay spectral studies to determine the feasibility of using these
glasses as luminescent devices in the visible region. The XRD standard confirmed the amorphous nature of
the prepared glasses. By means of the infrared spectra the vibrational characteristics of the borate glass groups
were verified. The characterization showed that the levels of rare-earth ions did not compromise the structural
properties of the glassy matrixes. Excitation and luminescence spectra and fluorescence lifetime of the
rare-earths ions were also detected. The excitation and emission spectra of both glasses show a broad PL profile
due to the <sup>2</sup>F<sub>5/2</sub>&rarr; and 5d&rarr;4 ftransitions for Yb and Ce dopant, respectively.
    Keywords: Excitation;luminescence;spectra and fluorescence;life time of the rare-earths;ions;characterization