Fig. 4: Periodic two-dimensional arrays of meta-atoms equivalent in their optical reflection properties to bulk metamaterials.
From: Optical Tellegen metamaterial with spontaneous magnetization
In each illustration, only one supercell is shown. a Oriented and (b) effectively random arrays of Tellegen meta-atoms, equivalent to anisotropic and isotropic Tellegen metamaterials, respectively. The macroscopic Tellegen response vanishes if the magnetization in the meta-atoms is global which is the case in c or if the meta-atoms have inversion symmetry which is the case in d or e.
