Gd 2 O 3 -modulated borate glass for the enhancement of near-infrared emission via energy transfer from Gd 3+ to Nd 3 .

(Li 2 O) 0.20 (SrO) 0.30 (Nd 2 O 3 ) 0.01 (B 2 O 3 ) 0.49- x (Gd 2 O 3 ) x , where x = 0, 3, 5, 7, and 10 mol%, glass was melt-quenched to test it as a laser source in the near-infrared (NIR) region. The structural modification, absorption spectra, Judd-Ofelt (J-O) parameters, luminescence spectra, radiative laser parameters, lifetimes, XRD, and FTIR spectra were studied. Luminescence spectra excited at λ exc = 584 nm revealed the highest intensity peak at 1073 nm due to the transition of 4 F 3/2 → 4 I 11/2 . An important phenomenon of concentration quenching was observed and optimized luminescence was achieved with the sample having the concentration x = 07 mol%. The lifetimes of the donor and acceptor and energy transfer from gadolinium to neodymium were obtained from the luminescence decay kinetics. The findings show that Nd-doped Gd 2 O 3 -modified glass materials have potential as NIR laser sources.