Homogenization Models for a Simple Dielectric-Composite Slab upon Oblique Incidence

Figure 3

The outermost boundary layer permittivities 𝜀_𝑏1 and 𝜀_𝑏2 of a 5-layer slab versus 𝜀_eff of the H-model for the 2-layer and 5-layer slabs. The field averaging method [21] is applied to compute these curves. As defined in Section 2, 𝑓₂₀ is the frequency when the effective wavelength 𝜆_eff in the slab is 20 times the length of the unit cell 𝑎. The quantity 𝑓/𝑓₂₀ then not only represents frequency, but also roughly indicates the ratio between 𝜆_eff and 𝑎. For instance, if 𝑓/𝑓₂₀ = 2, then 𝜆_eff≈10𝑎.