Investigation of Electromagnetic Characteristics of Toroidal Dipole based on Metamaterial under Terahertz Frequencies

Toroidal dipole response was observed by four U-SHAPE Metamaterial at terahertz frequencies, this shows that the toroidal dipole can be produced through the arrangement of four double U- SHAPE metamaterial as meta-atoms by manipulating the form properly meta-atoms. The experiment shows that the toroidal resonance gives subwavelength-scale electromagnetic, the electromagnetic field distribution and the surface current distribution were observed through the simulation of the electromagnetic field, and the toroidal dipole is observed from the magnetic field distribution map. The structure consists of the most advantage S- parametersa=168m, b=104m, w=18m, lx=152m, ly=60m, thm=0.4m, g=15m, t= 22m, s=5m. The transmission curve of the Metamaterial is observed in the (0.2 to 1.0) THz band. The transmission curve shows two main resonant valleys, respectively at the Low-frequency F=0.416THz and the High-frequency F=0.865THz. In the frequency F=0.865THz The toroidal geometry together with the Fano resonance of four U-SHAPE metamaterial induced strong toroidal dipole response will have enormous potential applications such as invisibility cloaks, superlenses, and devices with negative indices of refraction.