Intra-connected three-dimensionally isotropic bulk negative index photonic metamaterial

TL;DR

This paper demonstrates a proof-of-principle design for a fully isotropic three-dimensional negative index metamaterial at optical wavelengths, overcoming previous limitations of two-dimensionality and connectivity constraints.

Contribution

It introduces a novel design approach showing that connectivity constraints do not prevent the creation of 3D isotropic negative index metamaterials.

Findings

Achieved fully isotropic negative index behavior in 3D optical metamaterials.

Demonstrated the feasibility of fabricating 3D isotropic NIMs using direct laser writing.

Paved the way for ultra-high resolution 3D optical lenses.

Abstract

Isotropic negative index metamaterials (NIMs) are highly desired, particularly for the realization of ultra-high resolution lenses. However, existing isotropic NIMs function only two-dimensionally and cannot be miniaturized beyond microwaves. Direct laser writing processes can be a paradigm shift toward the fabrication of three-dimensionally (3D) isotropic bulk optical metamaterials, but only at the expense of an additional design constraint, namely connectivity. Here, we demonstrate with a proof of-principle design that the requirement connectivity does not preclude fully isotropic left-handed behavior. This is an important step towards the realization of bulk 3D isotropic NIMs at optical wavelengths.