Antenna Integrated THz Uni-Traveling Carrier Photodiodes

High-speed photodiodes are a key element of numerous photonic systems. With the development of potential applications in the THz range such as sensing, spectroscopy, and wireless transmission, devices with integrated antenna covering the frequency range from 0.1 to 3 THz will become essential. In this paper, we discuss the development of uni-traveling carrier photodiodes with integrated antennas to address that need. In particular we develop the key elements to present a simple design tool for the efficient integration of the device with an antenna. We also present fabricated device results that show the highest figure of merit to date for photonic THz emitters. When integrated with well-matched antennas the devices have achieved record level of power up to 1 THz compared to other published photomixers. We also show that these devices can be used as receivers at frequencies up to 560 GHz with conversion losses of the order of 30 dB.