Frequency tunability of terahertz photonic transmitters

摘要

In this study we investigated the frequency tunability of an edge-coupled membrane photonic transmitter. Its frequency tunability was found to be determined, not only by the radiation loss of the device and antenna pattern, but also by the frequency response of the photodetector. With a properly designed device pattern with a slot dipole antenna, which is known to have a strong resonant peak, both high-power conversion efficiency and a broadband response can be achieved. A wide frequency tuning range from < 100 GHz up to 1.1 THz is demonstrated from a single terahertz photonic transmitter. Combined with coherent-controlled quasicontinuous-wave optical excitation, this optoelectronic-based device also exhibits a record-high light-THz power-conversion efficiency of 0.33%.