Design of amplifier- and modulator-integrated laser diode for 10-Gb/s 80-km transmission

We present the amplifier- and modulator-integrated laser diode designed for 10-Gb/s transmission over 80-km distance. An antireflection window structure is implemented at the tilt facet of the amplifier to reduce optical feedback by 40 dB. A monitor photodiode is monolithically integrated in the antireflection window region for accurate power regulation. To better control the amplifier input power and to reduce the feedback of amplified spontaneous emission, an attenuation inner-window is incorporated by removing a section of the waveguide. The reproducibility of the chip fabrication process is tested to confirm the design margin. Through amplifying the modulated signals and reducing modulator chirp by amplifier saturation, high-power optical transmission is demonstrated.