Enhancement 2.0 μm fluorescence properties of Er3+/Ho3+ co-doped borosilicate glasses in the presence of Li+ ions for mid-infrared lasers

Abstract The effect of Li+ ion concentration on mid-infrared (MIR) emission of Ho3+/Er3+ co-doped borosilicate glasses was reported. X-ray diffractometer (XRD) curves confirmed the amorphous structure of the glass. With the introduction of Li+ ions, the [BO3] in the glass network structure was observed to increase while the destruction of [BO4]. The introduction of Li+ ions will make the distance between Er3+ ions and Ho3+ ions in the glass structure closer. The increase of Li+ ions will lead to the polarization of Er3+ ion electron cloud, which is conducive to the energy transfer between Ho3+ and Er3+ as well as the enhanced the emission of 2.0 μm with a full-width at half-maximum (FWHM) of 192 nm. According to the fluorescence decay curve, the energy transfer efficiency of Li+ ion doped sample is up to 80.1%. These above results indicate that the prepared sample is a potential substrate for 2.0 μm MIR lasers.