Enhanced absorption efficiency of ultrathin metamaterial solar absorbers by plasmonic Fano resonance

Abstract

We demonstrate a proof of principle that plasmonic Fano resonance can provide a complementary enhancement mechanism boosting the absorption efficiency of thin metamaterial solar absorbers over a wide angle of incidence under both TE and TM polarizations. Fano resonances are induced in arrays of two asymmetric metallic nanodimers coupled to a metallic layer through an intermediate insulator thin film. The resulting moderate resonant peaks shown in the scattering spectrum are predicted to play a dominant role in light-trapping enhancement.