Figure 1

Schematic of plasmonic nanohole array covered by a single layer of graphene (SLG). (a) Nanohole array substrate with 350 nm lattice constant on polymer substrate (n = 1.56) supporting a SLG. A fraction of graphene surface is covered with water droplets. (b) Optical image of the sample shows that some regions on the surface of SLG are covered with water. (c) Cross-sectional view of one unit cell of the nanostructure. The thicknesses of silver and titanium layers are 90 nm and 9 nm, respectively. Nanoparticles are 40 nm in diameter. The cup depth h is 500 nm. Top and bottom hole diameters are 200 nm and 160 nm, respectively. (d) Top view (top) and cross-sectional view (bottom) SEM images of the nanohole array substrate. (e) SEM images of the nanostructure partially covered with water droplets.