Analysis of terahertz wave reflection by an array of double dielectric elements placed on a reflective substrate

We numerically investigate the resonance properties of the reflective metasurface, which is a planar, two-direction lattice of pairs of dielectric bars placed on a metal substrate. The structure is designed in such a way and with such sizes that in its subwavelength mode the first few lowest frequency resonances fall within the far infrared wavelength range. To study the physical processes in the metasurface, spectral characteristics, 3D vector plots and maps for electromagnetic fields in the structure are presented.