106-Gb/s Waveguide AlInAs/GaInAs Avalanche Photodiode with Butt-joint Coupling Structure

A waveguide AIInAs/GaInAs APD with the butt-joint coupling structure for 106-Gb/s PAM4 applications is demonstrated for the first time. A maximum 3-dB bandwidth of 38 GHz and high responsivity at unity gain of 0.90 A/W are exhibited at 1.55 µm. © 2022 The Author(s)