Three-Dimensional Photonic Metamaterials by Direct Laser Writing and Advanced Metallization Techniques

We have utilized a novel fabrication concept, i.e., direct laser writing in combination with chemical vapor deposition of silver, to realize three-dimensional metamaterials for optical frequencies. Some of the fabricated structures give rise to bianisotropy resulting in a cross-coupling of the electric and magnetic fields of an incident light wave. We have also presented two unit cell designs which show a negative refractive index at infrared frequencies

Negative-index bi-anisotropic photonic metamaterial fabricated by direct laser writing and silver shadow evaporation

We present the blueprint for a novel negative-index metamaterial. This structure is fabricated via three-dimensional two-photon direct laser writing and silver shadow evaporation. The comparison of measured linear optical spectra with theory shows good agreement and reveals a negative real part of the refractive index at around 3.85 micrometer wavelength - despite the fact that the metamaterial structure is bi-anisotropic due to the lack of inversion symmetry along its surface normal.Comment: 8 pages, 3 figure