Enhanced ultra-wide NIR fluorescence in tellurite glass doped with Er3+-Tm3+-Nd3+-Ag NPs

Abstract

Tellurite glasses with combination of Er³⁺/Tm³⁺/Nd³⁺ ions and silver nanoparticles (Ag NPs) were prepared by using single-step melt-quenching technology, and the enhanced effect of Ag NPs on the ultra-broadband near-infrared (NIR) fluorescence was studied. Under the 808 nm LD excitation, two ultra-broadband NIR fluorescence of 1300-1600 nm and 1600-2100 nm underwent an obvious enhancement of about 52% compared to the tri-doping tellurite glass free of Ag NPs. The intensified local electric field induced by Ag NPs together with the energy transfer from Ag species to doped ions is responsible for this enhancement. The enhanced ultra-broadband NIR fluorescence of 1300-1600 nm with the full width at half maximum (FWHM) of 230 nm, originating from the spectral overlapping of 1.34 µm (⁴F_3/2→⁴I_13/2 of Nd³⁺), 1.47 µm (³H₄→³F₄ of Tm³⁺) and 1.53 µm (⁴I_13/2→⁴I_15/2 of Er³⁺) three bands, is promising in developing new ultra-broadband photonic devices such as fiber amplifiers and tunable lasers.

Keywords: Ag NPs; Er(3+)-Tm(3+)-Nd(3+) tri-doping; NIR enhancement; Ultra-broadband.