  We report systematic studies of plasmonic and photonic guiding modes in
large-area chemical-vapor-deposition-grown graphene on nanostructured silicon
substrates. Light interaction in graphene with substrate photonic crystals can
be classified into four distinct regimes depending on the photonic crystal
lattice constant and the various modal wavelengths (i.e. plasmonic, photonic
and free-space). By optimizing the design of the substrate, these resonant
modes can magnify the graphene absorption in infrared wavelength, for efficient
modulators, filters, sensors and photodetectors on silicon photonic platforms.
