Figure 1

Carbon nanotube metamaterial imaged under a scanning helium ion microscope. (a) The combinatorial sample consists of five metamaterial arrays with different unit cell sizes $D$ and an empty area annotated as “${\mathrm{Si}}_3{\mathrm{N}}_4$ window” on the same substrate. (b) The metamaterial structure is an array of slits in a gold film supported on a ${\mathrm{Si}}_3{\mathrm{N}}_4$ membrane. (c) CNTs deposited on the surface of the metal nanostructure form a layer of “nanoscale feutre.” Plates (d) and (e) show unit cells of the metamaterial before and after deposition of nanotubes. On plate (e) note the arrow pointing at a single nanotube crossing the slit. Plate (f) shows a milled slit manufactured to study the morphology of the structure, which is presented in plate (g).Reuse & Permissions

Figure 2

Spectral response of the carbon nanotube metamaterial: transmission ($T$), reflection ($R$) and absorption ($A$) for a metamaterial array with a $D=731\mathrm{nm}$ unit cell size (a) and for the same metamaterial fuctionalized with CNTs (b). Note the redshift of the plasmon absorption resonance in the CNT-fuctionalized metamaterial.Reuse & Permissions

Figure 3

Electronic density of states (DOS) in a semiconductor single-walled CNT (a); plasmonic absorption resonance in a metamaterial without CNTs and excitonic resonances in a CNT film on a silicon nitride substrate (b); simulated (COMSOL 3.4) color coded field map showing the total magnitude of the electric field of the light wave in the immediate proximity of the metamaterial plane at the plasmonic resonance ${\lambda }_p$ (c); and the dependence of the metamaterial absorption resonance spectral position on the unit cell size before and after functionalization with CNTs (d).Reuse & Permissions

Figure 4

Light-induced change of transmission of the CNT-functionalized metamaterial for different unit cell sizes (a). Light-induced transmission change for different levels of intensity for a CNT-functionalized metamaterial with unit cell size $D=839\mathrm{nm}$ (b). The nonlinear response of CNTs on a silicon nitride membrane (magnified by a factor of 100) is shown for comparison on panel (b) and also on panel (a) (without magnification).Reuse & Permissions

Figure 5

(a) Illustrative model of the CNT metamaterial and the plasmon-exciton nonlinearity. (See text and supplementary material [29] for more details.) (b) Linear dissipation of the uncoupled plasmon (red line) and exciton (blue line) systems. (c) Dissipation losses of the linked plasmon-exciton system at different levels of excitation.Reuse & Permissions