220-GHz high-speed photodetector and its demonstration of fiber wireless communications

We designed and fabricated a high-speed photodetector (PD) operating at 220 GHz using a uni-traveling carrier PD structure. In demonstrating its usage in fiber wireless communication, we successfully achieved 20 Gbps (non-return-to-zero: NRZ) high-data-rate communication using an intermediate frequency of 196 GHz at a distance of 20 cm. This paper describes the design and demonstration of the device in detail.