Fig. 8. Normal-incidence optical transmission spectra of biaxially corrugated graphene structures on SiO2 nanosphere arrays with DS = 60 nm and (a) a close-packed curvature pattern, (b) a graphene gap Gg, and (c) an air gap Ga of 5 nm when the refractive index of the sample medium atop the graphene surface nm changes from 1.3 to 1.5. The panels on the right compare the near-field intensity distributions at the plasmonic resonance wavelengths of the fundamental plasmon mode for the biaxially corrugated graphene structures denoted in (a)–(c) when nm = 1.3. (d) Scaling of the fundamental-mode resonant wavelength with respect to nm for structures denoted in (a)–(c).
