Size Effects in Periodic Metamaterials

The work studies how the optical behavior of periodic electromagnetic metamaterials depends on the ratio between the unit cell size (d) and the incident wavelength (λ). Using numerical calculations for realistic metamaterials, the authors compute reflection (R) and transmission (T) across a wide range of d/λ values, covering different operating regimes. They identify unusual features in how R and T vary and explain the causes of these peculiarities. Overall, the results are used to argue that homogenization is not applicable when the unit cell size is comparable to the wavelength, contrary to some earlier claims.