Complex Photonic Structures for Light Harvesting

Over the last few years, micro- and nanophotonics have roused a strong interest in the scientific community for their promising impact on the development of novel kinds of solar cells. Certain thin-and ultrathin-film solar cells are made of innovative, often cheap, materials which suffer from a low energy conversion efficiency. Light-trapping mechanisms based on nanophotonics principles are particularly suited to enhance the absorption of electromagnetic waves in these thin media without changing the material composition. In this review, the latest results achieved in this field are reported, with particular attention to the realization of prototypes, spanning from deterministic to disordered photonic architectures, and from dielectric to metallic nanostructures.