Tailoring lattice parameters for broadband artificial diamagnetism

We report a strategy to achieve the values of the effective magnetic permeability close to zero by using anisotropic metamaterial made of dense arrays of conductive loops. We present an extensive parametric analysis of the role of lattice parameters and symmetry, and also of the geometry of the loops. The magnitudes of the real part of the permeability reach 0.05 and are observed in a very broad frequency span, accompanied with negligible dissipation. Importantly, our analysis is applicable in a wide range of absolute sizes, being appropriate up to the THz range. Finally, we assess the dielectric properties of the optimal diamagnetic meta-materials, providing a complete picture of its interaction with the electromagnetic waves.