Monolithically integrated semiconductor optical amplifier and electroabsorption modulator with dual-waveguide spot-size converter input

We have demonstrated a semiconductor optical amplifier and electroabsorption modulator monolithically integrated with a novel dual-waveguide spot-size converter at the input for low-loss coupling to planar lightguide circuit silica waveguides or cleaved single-mode optical fiber. These devices exhibit greater than 10 dB fiber-to-fiber gain, output power of +4 dBm, 3-dB modulation bandwidth of 6 GHz, and modulator extinction ratios of 20 dB dc and 14.4 dB RF for a 2.4-V/sub pp/ drive.