Highly efficient and tunable selective absorber design based on metallic nanoparticles in a graded index dielectric

We propose a novel solar selective absorber design based on transverse localized surface plasmon resonances of infinite metallic nanorods embedded in a graded index dielectric slab. The physics principles on which the design is based are explained, and decent results are obtained by numerical simulations; solar absorptance values exceeding 0.99 are reached together with a near-zero infrared emittance. The proposed structure design offers a flexible tunability of thermal emission, and this spectral control over thermal emission promises advances not only in solar energy harvesting efficiency, but also in sensing, camouflage, and other thermal management applications.