Energy Transfer Kinetics and Luminescence in Nd³⁺/Yb³⁺Co-Doped Lead-Borate Glasses at 800 nm Excitation

Nd³⁺ and Nd³⁺/Yb³⁺ ion-doped lead-borate glasses were created. For the thermal studies of sample such as glass transition temperature, crystallization temperature and, melting temperature Tm, differential scanning calorimetry (DSC) is done. The X-ray diffraction is used to justify the glassy nature of the samples. UV-VIS-IR of the prepared samples is carried for the studies of absorption bands available in Nd³⁺ and Nd³⁺/Yb³⁺ ion-doped lead-borate glasses. For the studies of fluorescence spectra and energy transfer mechanism the samples were excited at 800nm and spectra is recorded. The Nd³⁺ glasses exhibited strong NIR emission at 1mol% concentration at 903, 1068, and 1348 nm upon pumping at 800 nm. These transitions were labelled as ⁴F3/2→⁴I9/2, ⁴F3/2→⁴I11/2, and ⁴F3/2→⁴I13/2. Interpretation is given to the effects of multiphonon, cross-relaxation, and OH- group on Nd³⁺ emission that causes photoluminescence quenching above 1.0mol% Nd³⁺. Through the co-doping of Nd³⁺ ion (1mol%) and Yb³⁺ ion (1mol%) concentrations, the sensitising impact of Nd³⁺ emission on Yb³⁺ luminescence is examined. The significant spectrum of Yb³⁺ absorption and Nd³⁺emission, photoluminescence characteristics, has supported the likelihood of energy-transfer (ET) between these ions. The findings show that the Neodymium ion (⁴F3/2)→ytterbium ion (⁴F5/2) energy-transfer process is of a non-radiative type controlled by phonon-assisted electric dipole-dipole interaction.