Figure 4. Optical properties of NPG at fixed Fermi energy for different pore size.

(a,b) SEM images of nanoporous graphene samples with the same average Fermi energy E_F∼70 meV, and decreasing pore size. Scale bar corresponds to 1 μm. (d–f) corresponding optical conductivity curves (pore size decreases from a–c). The whole fitting (see equation (1) in the text), and the plasmon and interband components are represented by blue-dashed, blue dotted and green dotted lines, respectively. NPG, nanoporous graphene; SEM, scanning electron microscope.