SINX/AL METAMATERIAL-BASED TERAHERTZ-TO-INFRARED CONVERTER FOR REAL TIME IMAGING - Video Portal
SINX/AL METAMATERIAL-BASED TERAHERTZ-TO-INFRARED CONVERTER FOR REAL TIME IMAGING
Sangmin Lee, LCDR, Korean Navy
The terahertz (THz) real time imaging technology can used in various fields. One attractive way to perform real time THz imaging is through metamaterial-based MEMS focal plane arrays (FPA). Among different possible configurations, THz-to-IR converters were selected to be studied and developed. The operation principle is using an infrared camera to image the heat pattern on the backside of the FPA, generated by the absorption of the THz scene, presented on the front side of the FPA. In this study, we design and fabricate metamaterials that efficiently absorb 3.8 THz and 4.75 THz, which are the frequencies of the quantum cascade lasers available in the Physics Department. In addition, metamaterials that have near 1 emissivity between 20 and 40 THz and near zero elsewhere were designed. To develop this sensor, the properties of silicon nitride (SiNx) films were investigated using single square unit cells. Next, the geometric configuration of the metamaterial elements were designed using the COMSOL Multiphysics and CST Microwave studio. Finally, the metamaterials were fabricated using tools available in the NPS microfabrication facility (Clean Room). The optimized metamaterial films, obtained during thesis work will be used in an optimized THz-to-IR converter to be integrated to a long wave infrared camera in order to provide a complete THz imaging system.