  A tri-layer metamaterial perfect absorber of light, consisting of (Al/ZnS/Al)
films with the top aluminium layer patterned as an array of circular disk
nanoantennas, is investigated for resonantly enhancing Raman scattering from
C-60 fullerene molecules deposited on the metamaterial. The metamaterial is
designed to have resonant bands due to plasmonic and electromagnetic resonances
at the Raman pump frequency (725 nm) as well as Stokes emission bands. The
Raman scattering from C60 on the metamaterial with resonantly matched bands is
measured to be enhanced by an order of magnitude more than from C60 on
metamaterials with off-resonant absorption bands peaked at 1090 nm. The Raman
pump is significantly enhanced due to the resonance with a propagating surface
plasmon band, while the highly impedance matched electromagnetic resonance is
expected to couple out the Raman emission efficiently. The nature and
hybridization of the plasmonic and electromagnetic resonances to form compound
resonances are investigated by numerical simulations.
