High-Responsivity Semimetal Terahertz Detectors Based on Localized Surface Plasmon Resonance Effect

In this letter, we demonstrate a novel silicon dual microdisk Cd3As2 terahertz detector. The introduction of the silicon dual microdisk structure brings the localized surface plasmon resonance (LSPR) effect, significantly enhancing the responsivity of the semimetal terahertz detector. The fabricated Cd3As2 terahertz detector, with parameters optimized through simulation, exhibits a responsivity of 0.6791A/W under broadband terahertz irradiation spanning from 0.26THz to 0.4THz. This approach provides an innovative strategy for improving the performance of detectors in the low-frequency terahertz range and promotes the research of semimetal-based terahertz detectors.