Suppression of scattering loss in Erbium-Yttrium Silicate crystalline waveguide fabricated by radical-assisted sputtering

Er 0.45 Y 1.55 SiO 5 crystalline waveguide burying Si-guide stripe was fabricated by radical-assisted sputtering (RAS). We evaluated the light propagation properties with pumping at 1.48m. The light propagation loss drastically decreases by 82 cm −1 in the RAS waveguide compared with the previous waveguide by sol-gel.