High-performance waveguide-coupled lateral Ge/Si avalanche photodetector.

A high-performance waveguide-coupled lateral avalanche photodetector (APD) is experimentally demonstrated without silicon epitaxy and charge layer ion implantation. At the wavelength of 1550 nm, it shows a high responsivity of 48 A/W and a gain-bandwidth product (GBP) of 360 GHz. Wide-open eye diagrams at 25 Gbps can be observed at various avalanche gains. These outstanding performances indicate the proposed APD has great potential in high-speed optical transceivers for optical links.