4-Channel Distributed Bragg Reflector Laser Array Integrated with 10-Gbps Electroabsorption Modulator

A 4-channel wavelength division multiplexing transmitter was fabricated with an array of distributed Bragg reflector (DFB) lasers monolithically integrated with 10-Gbps electroabsorption (EA) modulators. A selective area growth technique was employed for the control of bandgap energy in the gain and modulator sections. Then the laser and modulator stripes were fabricated by a buried heterostructure process. The DBR lasers showed uniform threshold currents between 5-10 mA , while the slope efficiency was around 0.11 W/A. By controlling the DBR currents, a 4-channel transmitter was achieved for the channel spacing of 100 GHz (0.8 nm). The 3-dB bandwidth of the EA modulator was measured to be over 10 GHz for all bias voltages. The EA modulator showed clear eye openings under 10-Gbps non-return-to-zero modulation. It allowed 10-Gbps error-free operation over a 25-km long single mode fiber.