White light emission of dysprosium doped calcium-lanthanum-borate glass

The starting material was melted at 1,100-1,300 °C in an air atmosphere and then naturally cooled, and Ca(La1-xDyx)B7O13 (x = 0.01-0.30), MII(La0.94Dy0.06)B7O13 (MII: Mg, Ca, Sr, Ba), Ca(REIII0.94Dy0.06)B7O13 (REIII: La, Gd, Y) and Ca(La0.94Dy0.06)ByO13 glasses were produced. Fluorescence peaks were observed at 483 nm (4F9/2 → 6H15/2) and 574 nm (4F9/2 → 6H13/2) at an excitation wavelength of 351 nm for all glasses. The fluorescence peak intensity at 483 nm and 574 nm of Ca(La1-xDyx)B7O13 glass increased with increasing Dy content at x = 0.01 to 0.06. On the other hand, it decreased at x = 0.06 or more, confirming the concentration quenching. The chromaticity coordinate at x = 0.06 was (0.295, 0.346). In the MII(La0.94Dy0.06)B7O13 glass, the fluorescence intensity of Mg was slightly stronger than that of Ca, Sr and Ba. Moreover, in Ca(La0.94Dy0.06)ByO13 glasses, the intensity at y = 3-6 was slightly stronger than that at y = 7. It is considered that the low symmetry around Dy3+ has an effect.