Sm3+ photoluminescence and excited-state dynamics in lithium-barium borate glasses co-doped with CuO

Abstract

• Lithium-barium borate glasses containing Sm 2 O 3 and CuO prepared by melting. • Characterizations performed by XRD, FT-IR, UV/Vis/NIR and photoluminescence spectroscopies. • Influence of CuO on Sm 3+ luminescence investigated through PL decay kinetics. • Efficient Sm 3+ → Cu 2+ energy transfer indicated due to strong spectral overlap. The effect of CuO co-doping on orange/red-emitting Sm 3+ -doped borate glasses prepared by melting was investigated by various spectroscopic techniques. The glasses were first characterized by X-ray diffraction and Fourier transform-infrared spectroscopy for basic structural properties. Absorption spectroscopy showed that CuO addition leads to the development of the Cu 2+ absorption band around 735 nm. Photoluminescence (PL) spectra obtained for the CuO-free reference glass under 250 nm excitation displayed host-sensitized Sm 3+ PL along with intrinsic band emission from the borate host. The CuO doping produced a new contribution to band emission characteristic of Cu + . Further, significant decrease of Sm 3+ visible luminescence was evidenced in accord with a quenching effect induced by Cu 2+ . The analysis of Sm 3+ emission decay curves harmonized with the occurrence of two populations of Sm 3+ ions (single, interacting). The two decay components showed significant 4 G 5/2 lifetime decrease with increasing CuO content demonstrating an efficient Sm 3+ → Cu 2+ energy transfer.