Hyperbolic metamaterial feasible for fabrication with direct laser writing processes

Stimulated-emission-depletion-microscopy-inspired direct laser writing (STED-DLW) processes can offer diffraction-unlimited fabrication of 3D structures, not possible with traditional electron-beam or optical lithography. We propose a hyperbolic metamaterial for fabrication with STED-DLW. First, we design meandering wire structures with three different magnetic dipoles which can be excited under different incidences of light. Then, based on effective parameters corresponding to normal incidence and lateral incidence, we find that the hyperbolic dispersion relation for a five-layer structure appears between 15 and 20 THz. Finally, we investigate the influence of imaginary parts of the effective parameters on the metamaterial dispersion. The proposed metamaterial structure also has potential for three-dimensionally isotropic permeability despite geometric anisotropy.