Highly Sensitive, 112 Gb/s O-Band Waveguide Coupled Silicon-Germanium Avalanche Photodetectors

We present two different waveguide coupled SiGe APDs. We report 25 Gb/s error free operation with −12 dBm input power. Additionally, 112 Gb/s PAM-4 operation below the KP4-FEC threshold of 2.0 × 10 −4 is reported.