Rare-earth-ion-doped Al₂O₃ for integrated optical amplification

Erbium-doped aluminum oxide channel waveguides were fabricated on silicon substrates and their characteristics were investigated for Er concentrations ranging from 0.27 to 4.2x10e20 cm-3. Background losses below 0.3 dB/cm at 1320 nm were measured. For optimum Er concentrations in the range of 1 to 2x10e20 cm-3, internal net gain was obtained over a wavelength range of 80 nm (1500-1580 nm) and a peak gain of 2.0 dB/cm was measured at 1533 nm. 170 Gbit/s high-speed data amplification was demonstrated in an Al2O3:Er3+ channel waveguide with open eye diagrams and without penalty. A lossless 1x2 power splitter has been realized in Al2O3:Er3+ with net gain over a wavelength range of 40 nm (1525-1565 nm) across the complete telecom C-band.