Terahertz Photomechanical Detector Based on Meta-surface Absorber and Enhanced Cantilevers

Terahertz focal plane array imaging system has attracted much attention nowadays, this paper proposes a photomechanical terahertz detector, which is ideal for forming the focal plane array. The detector works at room temperature, and a meta-surface absorber is used to couple the incident terahertz radiation, so that a coupling efficiency higher than 90% can be obtained from 2.7 to 3.46THz. The bi-material cantilevers will produce a deformation corresponding to incident power, and the responsivity of detector is R=12.2μm/μW with a response time of 90ms. Thermal isolation between pixels is also considered and realized by introducing heat-insulating cantilevers.