Abstract

A spectroscopic investigation of sodium germanate glasses activated with Ce3+, Tb3+ and Ce3+/Tb3+ is carried out by analyzing their photoluminescence spectra and decay times. Non-radiative energy transfer from Ce3+ to Tb3+ is observed upon near-UV excitation at 310nm (peak emission wavelength of AlGaN-based LEDs). The non-radiative nature of this energy transfer is inferred from the increase in the decay rate of the Ce3+ emission when the glass is co-doped with Tb3+. From an analysis of the Ce3+ emission decay time curve it is inferred that an electric dipole–quadrupole interaction might to be the dominant mechanism for the Tb3+ emission sensitized by Ce3+. Energy transfer from Ce3+ to Tb3+ leads to a simultaneous emission of these ions in the blue, green, yellow and red, resulting in white light with CIE1931 chromaticity coordinates, x=0.30 and y=0.32, which correspond to cold white light with a colour temperature of 7320K and very small deviation from the Planckian black-body radiator locus (0.005).

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.