High-Speed Pin-Traveling Wave Photodetector Based on a Semiconductor Optical Amplifier Layer Stack on Semi-Insulating Inp Substrate

Abstract

Abstract-We present a pin-Traveling wave Photodetector (TWPD) on semi-insulating (SI) InP substrate at 1.55 µm wavelength window with an electrical bandwidth of more than 120 GHz, a line characteristic impedance of about 50 Ω, and microwave index matched to the optical group index. The internal quantum efficiency more than 99% for a 200 µm long device is determined. The layer stack of the TWPD has previously utilized in a semiconductor optical amplifier (SOA). The TWPD can be monolithically integrated with passive and active components such as arrayed waveguide grating (AWG), MachZehnder Interferometer (MZI), laser and modulator.