Journal Article

Realization of mid-infrared graphene hyperbolic metamaterials

Marder, Seth R., Zhang, Siyuan, Narimanov, Evgenii E., Liu, Chang-Hua, Zhong, Zhaohui, Chang, You-Chia, Liu, Che-Hung, Norris, Theodore B.

2016

Overview

While metal is the most common conducting constituent element in the fabrication of metamaterials, graphene provides another useful building block, that is, a truly two-dimensional conducting sheet whose conductivity can be controlled by doping. Here we report the experimental realization of a multilayer structure of alternating graphene and Al 2 O 3 layers, a structure similar to the metal-dielectric multilayers commonly used in creating visible wavelength hyperbolic metamaterials. Chemical vapour deposited graphene rather than exfoliated or epitaxial graphene is used, because layer transfer methods are easily applied in fabrication. We employ a method of doping to increase the layer conductivity, and our analysis shows that the doped chemical vapour deposited graphene has good optical properties in the mid-infrared range. We therefore design the metamaterial for mid-infrared operation; our characterization with an infrared ellipsometer demonstrates that the metamaterial experiences an optical topological transition from elliptic to hyperbolic dispersion at a wavelength of 4.5 μm. The use of graphene can provide another useful building block for metamaterials. Here, Chang et al . have explored the experimental realization of a mid-infrared hyperbolic metamaterial, in which the role of the metal in providing a conducting layer is taken over by graphene.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
• Subject: 132/122 / 639/301/357/918 / 639/766/400 / 639/925/357/1015 / Computer engineering / Conductivity / Fabrication / Graphene / Humanities and Social Sciences / Metals / multidisciplinary / Optical properties / Science / Science (multidisciplinary) / Semiconductors