Study on Er3+-Yb3+ co-doped La2O3–Al2O3 glasses for C-band optical waveguide amplifier with high luminous efficiency and low pump threshold

Efficient planar optical waveguide amplifiers at C-band are critical to the development of silicon photonics. In order to overcome the problem of low utilization efficiency of 980 nm pump for erbium-based planar optical waveguide amplifiers, an Er3+-Yb3+ co-doped La2O3–Al2O3 glass material for optical waveguide amplifiers was developed in this paper. While maintaining a high Er3+ doping concentration (∼1021 cm−3), the utilization efficiency of the material for 980 nm pumping is improved, so that the pump threshold of the waveguide amplifier fabricated with this material is lowered. Moreover, up-conversion and down-conversion luminescence are also suppressed in the material, resulting in a significant increase in the luminescence intensity of the C-band. A simple ridge waveguide simulation suggests that waveguide amplifiers fabricated by this material are expected to surpass the highest net gain reported so far for erbium-based planar waveguide amplifiers.