Plasmonic photoconductive antennas for high-power terahertz generation and high-sensitivity terahertz detection

High power sources and high sensitivity detectors are in demand for any terahertz imaging and sensing system. Incorporating plasmonic contact electrodes in photoconductive terahertz sources and detectors has proved to offer higher terahertz radiation powers and detection sensitivities by enhancing the photoconductor quantum efficiency significantly. This is because of the unique capability of plasmonic electrodes in manipulating the concentration of photocarriers near photoconductor contact electrodes, allowing a larger number of photocarriers reach photoconductor contact electrodes within a terahertz oscillation cycle to efficiently contribute to terahertz radiation and detection. The impact of plasmonic electrodes on enhancing the output power and detection sensitivity of photoconductive terahertz sources and detectors is universal and can be employed in various types of photoconductive terahertz antennas, as summarized in this article.