Silicon-Based Plasmonic Nanoantennas at mid-infrared for Gas Sensing Applications

Advanced nanotechnology especially CMOS technology-enables us to re-design the classic antenna in the nanoscale, which can convert propagating optical wavelengths instead of radio and microwave wavelengths into localized energy and vice versa. As a result, sensors may be designed to make sensing molecules with their characteristic vibrational transitions easier. Bowtie silicon nanoantennas are investigated in this work. When silicon with high excess carrier concentrations is used as the material of choice, the enhancement occurs in the mid-IR (MIR) spectral range, which is red-shifted when compared to the enhancement produced when gold or silver is used. Varying the substrate material and associated resonance wavelength influences the localized electric field.