Fabrication Technique Of Yb: Er Co-doped Al₂O₃ Waveguide Amplifiers, Theoretical Design Of Non-uniform Er Doped Waveguide Amplifier

Yb:Erco-doped Al₂O₃ thin films have been prepared by Middle frequency sputtering (MFS)and microwave electron cyclotron resonance plasma plasma source (ECR-MW). Ratio of O₂ and Ar, photolumiscence intensity, optimal ratio of Yb:Er, optimal annealing temperature, topograph of sample have been studied. Optimal optical property of sample fabricated by MFS has been achieved at O₂ 25-45sccm, Ar 70sccm, under 850℃ annealed, and ratio of Yb:Er 9:1; Optimal optical property of sample fabricated by MFS has been achieved at O₂ 20sccm, Ar 20sccm, under 900℃ annealed, and ratio of Yb:Er 5:1.Rib-waveguides have been developed based on thin films employing plasma etching. Width of rib waveguides prepared by MFS is 4μm, height of waveguide is 1.0-1.2μm. Width of rib waveguides prepared by ECR-MW is 4μm, height of waveguide is 0.4-0.6μm. Gain of waveguide has been measured by designed opto-electric system: 7.826dB is obtained from 15mm waveguide prepared MFS, the average gain 5.217dB/cm; 2.385dB is obtained from 15mm waveguide prepared ECR-MW, the average gain 1.59dB/cm. Under same pump powers, gain output of rib-waveguide is high than that of planar waveguide.Non-uniform doped waveguide amplifiers are proposed. 6 Er energy levels and 2 Yb energy levels are included and cooperative upconversion, cross relaxation, excited state absorption are involved. Non-uniform Er and Yb:Er co-doped waveguide are designed based on two kinds of ions concentration by self-adapted method, and 2.25% and 7.26% improvements have been achieved. Laser annealing treatment has been proposed for Er:Al₂O₃. Details about experiment are improved, and PL intensity of Laser annealing is 47 times higher than 900°C heat treatment. Laser annealing is supposed to be applied to non-uniform EDWA and YEDWA.