(a). Sample picture of an array of symmetrical meta-atoms with a₁ = 4 mm, b₁ = 5 mm, c₁ = 2.2 mm, (see inset). The thickness and width of metallic wires are and , respectively. Spectra of (b) reflection phases and ) and (c) normalized reflectance for the sample shown in (a), obtained by experiments (symbols) and FDTD simulations (line). Here, represents the total reflected energy summing up contributions from all four terms in Equation 2, and the gray region in (b) and (c) indicates the working band of our sample which is determined by the condition of . All figures reproduced with permission from [24] .© 2015, Wiley-VCH