Cross-slot nano-antenna with graphene coat for bio-sensing application

we present a compact cross-shaped nano-aperture for biomedical and spectroscopy applications. Furthermore, by adding a graphene coat to structure, we achieved a reconfigurable particle with more transmittance. Finally, a cross shape chain of silicon dioxide is added to structure and it is placed on graphene layer and over the aperture slot. The structure is modeled with FDTD simulation by the CST microwave studio and for substrate, we selected SiN with n=1.98 and thickness of 80 nm. The palik model is used for gold layer with thickness of 30 nm and the 2 nm graphene layer is selected for coat. The simulations emphasize that adding graphene coat and silicon dioxide chain is applicable in order to improve the transmittance at mid infrared (IR) frequency. In addition, here we show that the chain structure is useful for enhancement of the E-field in both X and Y direction and it is made useful this particle for energy harvesting. Figure of merit (FOM) is studied for different additional material effects on prototype structure and ∆(E) variation. Finally, we revealed that the current device is highly practical for making differential sensor for detecting nano-particle with more accuracy and sensitivity.