Luminescence and absorption of Tb3+in mo·Al2O3·B2O3·Tb2O3 glasses

Quantum yields of the green Tb luminescence for 254 nm excitation of glass compositions in the system MO·Al2O3· B2O3·Tb2O3 (M = Mg, Ca, Sr, Ba and Zn) were studied in relation to absorption and excitation spectra. Yields as high as 80% were observed. The Tb 4f-5d absorption maximum ranges from 218 to 232 nm, always at a longer wavelength than the glass matrix absorption. The yield strongly depends on the spectral position of the 4f-5d absorption, due to competing impurity absorption at 254 nm.