Self-Rolling SiO2/Au Based Epsilon-Near-Zero Metamaterials

Wave propagation in epsilon-near-zero (ENZ) media offers exciting possibilities in the field of nanophotonics. Here, a thin film self-rolling technique to fabricate SiO2/Au based 3D multilayer structures is implemented. These cylindrical multilayer metamaterials are utilized to take advantage of the material dispersion as well as the structural dispersion to obtain self-rolling ENZ metamaterials at the visible to near-infrared wavelength range. The ENZ features are investigated initially by modelling the dispersion of the effective medium using circular effective medium approximation and further by the characterization of the optical response. Moreover, the potential of these structures for supporting an ENZ waveguide mode is demonstrated. This platform for dispersion engineering and obtaining ENZ metamaterials can provide opportunities for unique applications which cannot be possible with planar systems. It can be used to integrate active materials before the rolling process to actively control the layer properties, or embed single-layer materials within different layers of ENZ metamaterials with potential applications in quantum nanophotonics.