Low-loss optical $Er3+$-activated glass-ceramics planar waveguides fabricated by bottom-up approach

A low-loss optical erbium activated silica-hafnia glass-ceramic planar waveguide was fabricated using a bottom-up approach. Hafnia nanoparticles were first prepared by colloidal route and then mixed in a silica-hafnia:$Er3+$ sol. The resulting sol was deposited on $SiO2$ substrate. Analysis of the photoluminescence has demonstrated that erbium ions are embedded in a crystalline phase. A lifetime enhancement of the $I13∕24$ metastable level was observed. Losses measurements at $1542nm$ highlight a very low attenuation coefficient $(0.3dB∕cm)$ making this nanostructured material suitable for single band waveguide amplifier in the C band of telecommunications.