Article

Luminescent studies of Dy 3+ ion in alkali lead tellurofluoroborate glasses

Journal of Quantitative Spectroscopy and Radiative Transfer (Impact Factor: 2.38). 01/2011; 112(1):78-84. DOI: 10.1016/j.jqsrt.2010.08.017

ABSTRACT Dy3+-doped alkali lead tellurofluoroborate (RLTB) glasses (R=Li, Na and K) were prepared by melt quenching technique. Judd–Ofelt theory has been used to evaluate the three intensity parameters Ω2, Ω4 and Ω6 from the experimental oscillator strengths. The photoluminescence spectra obtained by the excitation wavelength of 385nm show four emission bands at 454, 483, 575 and 665nm corresponding to the 4I15/2→6H15/2 and 4F9/2→6HJ/2 (J=15/2, 13/2 and 11/2) transitions, respectively. The laser characteristic parameters like fullwidth at half maxima (FWHM), stimulated emission cross-sections (σe), optical gain parameters (σe×τexp) and gain bandwidth parameters (σe×FWHM) were determined. From the visible emission spectra, yellow to blue (Y/B) intensity ratios and chromaticity coordinates were also estimated. The lifetimes of 4F9/2 metastable state were also measured and discussed.

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