High-speed (10-40 Gb/s) electroabsorption modulator integrated devices for fiber communications

In this talk, identical epitaxial layer high speed electroabsorption (EA) modulator integrated light sources are studied systematically. Firstly, a 1.55 μm 10 Gb/s distributed feedback (DFB) laser integrated EA modulated laser is presented, which adopts a partially gain-coupled DFB laser to improve single-mode yield. The typical measured small signal response indicates a 3 dB electrical bandwidth over 10 GHz. Secondly, a 1.55 μm laterally coupled DFB laser is fabricated to eliminate the necessity of additional regrowth, in order to reduce the process complexity and fabrication cost. A stable single-mode operation has been demonstrated with a side mode suppression ratio over 45 dB at an injection level of 60 mA. Finally, an SOA integrated EA modulator with a planar ridge waveguide is fabricated for 40 Gb/s optical fiber communication systems. The device is chip-level packaged and tested on a coplanar waveguide based submount. The small signal frequency modulation responses of the integrated EA modulator are measured and simulated based on an equivalent circuit. The measured 3 dBe modulation bandwidth exceeds 40 GHz, and it is estimated to be over 45 GHz.