Sub wavelength plasmonic nano-antenna with H and U shape for enhancement of multi resonance

In this article, Optical electric field enhancement in the normal direction is noticed. For this aim, we selected single H and U-shape array antenna, which are known as a conventional type of the nano-antenna. Both of these antennas are studied in their most common form and then combinations of these antennas are studied for achieving multi- band and improving absorption of the antenna. Here, for all structures, the E-field (electrical field) enhancement in the X direction is studied and design parameter effects on field enhancement are debated. The effect of antenna parameters on resonance frequency and Ex enhancement is studied in this article. In addition, we noticed the effect of the U elements arrangement on E-field enhancement in X direction. Therefore, in current research, the extinction cross section is studied for every structure and formation. For modeling the prototype structures, here SiN is selected for Substrate with n = 1.98 and silver with Johnson optical characteristic for metal layer. Simulation has been done in the time domain with CST microwave studio commercial software.