Photonic metamaterials by direct laser writing and silver chemical vapour deposition.
Metamaterials are artificial materials that--unlike natural substances--enable magnetism to be achieved at optical frequencies. The vast majority of photonic metamaterials has been fabricated by electron-beam lithography and evaporation of metal films, both of which are well-established two-dimensional (2D) technologies. Although stacking of three or four functional layers made using these methods has been reported, a truly 3D fabrication approach would be preferable for 3D photonic metamaterials. Here, we report first steps in this direction by using a combination of direct laser writing and silver chemical vapour deposition--the 3D analogues of electron-beam lithography and evaporation, respectively. The optical characterization of a planar test structure composed of elongated split-ring resonators is in good agreement with theory. Retrieval of the effective optical parameters reveals the importance of bi-anisotropy. Once suitable theoretical blueprints are available, our fabrication approach will enable rapid prototyping of truly 3D photonic metamaterials.
Rill
Michael S
MS
Institut für Angewandte Physik, Universität Karlsruhe (TH), D-76131 Karlsruhe, Germany.
Plet
Christine
C
Thiel
Michael
M
Staude
Isabelle
I
von Freymann
Georg
G
Linden
Stefan
S
Wegener
Martin
M