Effective sensitization of Yb3+ ions on Yb3+/Nd3+ co-doped fluoroborate glasses for NIR luminescence applications

Nd3+/Yb3+ co-doped fluoroborate glass samples were fabricated by melt quenching. The near infrared luminescence (NIR) spectral features of Nd3+/Yb3+ co-doped fluomborate glasses were characterized by XRD, SEM, FT-IR, optical absorption, photoluminescence (PL) and PL decay spectral studies. An effective energy transfer process has been observed from Nd3+ to Yb3+ in the titled glasses under 808 nm excitation wavelength. Broad , emission ranging from 850 to 1400 nm due to both Nd3+ (F-4(3/2)-> I-4(9/2),F-4( )3/2 -> I-4(11/2) and F-4(3/2)-> 4I(13/2)) and Yb3+ (F-2(5/2)-> F-2(7/2)) transitions has been observed in all the glasses. The dependence of NIR emission, decay lifetime, and the energy transfer efficiency (eta(ETE)) with the concentration of Yb3+ was studied in detailed. The PL spectra along with donor decay curves have been used to establish the energy transfer mechanism between Nd3+/Yb3+ ions. The results represent the possible sensitization of Yb3+ through 4f-4f transition of Nd3+ ions in titled glasses. The PL of the Nd3+ singly doped and Nd3+/Yb3+ co-doped titled glasses indicate their suitability as multiple pump channel sources for Yb3+ fiber laser systems. The results finally prove that the Nd3+/Yb3+ codoped fluoroborate titled glasses are quite useful to fabricate infrared laser gain materials.