title: Silicon-based traveling-wave photodetector array (Si-TWPDA) with parallel optical feeding.
abstract: We demonstrate silicon-based traveling-wave photodetector arrays (Si-TWPDAs) with parallel optical feeding by integrating multiple Germanium photodetectors. Such Si-TWPDAs feature the merit of high optical saturation power with remaining the large operation bandwidth. The impedance-matched traveling-wave electrode design takes into account the individual Ge photodetector loading effect. Optical waveguide delay lines are designed in order to balance the electrical phase delay of the traveling-wave electrode. The maximum linear photocurrent at -4V biased voltage are respectively 16 mA, 38 mA, and 65 mA with integrating 1, 2, and 4 photodetectors, upon the saturation power of 40 mW, 100 mW, and 160 mW. This corresponds to a normalized photocurrent generation of >0.32 mA/µm3 and a normalized saturation power of 0.8 mW/µm3. The extracted fiber access responsivity is ~0.42 A/W and the intrinsic responsivity of ~0.82 A/W. The measured 3-dB bandwidth for 4-channel TWPDA is ~20 GHz.
authors.forename: Xianshu
authors.initials: X
authors.lastname: Luo
authors.forename: Junfeng
authors.initials: J
authors.lastname: Song
authors.forename: Xiaoguang
authors.initials: X
authors.lastname: Tu
authors.forename: Qing
authors.initials: Q
authors.lastname: Fang
authors.forename: Lianxi
authors.initials: L
authors.lastname: Jia
authors.forename: Ying
authors.initials: Y
authors.lastname: Huang
authors.forename: Tsung-Yang
authors.initials: TY
authors.lastname: Liow
authors.forename: Mingbin
authors.initials: M
authors.lastname: Yu
authors.forename: Guo-Qiang
authors.initials: GQ
authors.lastname: Lo