Figure 1
The split ring resonator unit-cell using low resistivity copper (5.8 × 107 S/m) with dimensions a = 3 mm (λ/11.3 at resonance frequency GHz), d = 2.8 mm, w = 0.32 mm and g = 0.42 mm (a) and the simulated absorbance for normal incidence and for TE or TM polarization (b): only for the TM polarization does the geometry act as an absorber. Also depicted is the super-cell (c), consisting of four of the basis unit-cells, which are sequentially rotated by 90 deg and the simulated A for the latter structure, for normal incidence and for TE or TM polarization (d): identical A for both polarizations. The surface current distribution for the unit-cell, for TE (e) and TM (f) polarization and for the super-cell for TE (g) and TM (h) polarization, simulated at the corresponding resonance frequencies and for normal incidence, is also depicted: it is observed that the currents, which form loops are dominant in terms of their intensity, and these lead to absorption.
