Abstract
We report on a novel blue emission from pentavalent tantalum ions embedded into silicate glass host under ultraviolet (UV) irradiation. Optical absorption and fluorescence spectra were measured for undoped and tantalum-doped silicate glasses. An absorption band with large absorption coefficient appeared in UV wavelength region when tantalum ions were incorporated into glass host. The as-prepared sample exhibited highly enhanced blue emission when excited by UV photons, which seems that it is distinctly different from emission of defects. We suggest tentatively that the localized 5d0 energy level of Ta5+ is responsible for the appearance of the intense blue emission.
