Spatially modulated light harvesting with plasmonic crescent metasurface.

Harvesting light by metallic structures with sharp corners, or the so-called photonic singularities, has exhibit their potential in nanophotonics, sensing, and bio-medical applications. The high-quality light confinement of the light energy mainly relies on the precise preparation of nanoscale photonic singularities. However, the realization of massive photonic singularities still meets the challenges on integration and low-cost mask multiplexing. Here, we show an angle-dependent elevated nanosphere lithography to achieve massive photonic singularities for spatially modulated light harvesting at the near-infrared regime. The photonic geometrical singularity is constructed by the gold crescent array of plasmonic materials. The numerical simulation shows that the light can be localized at the spatially distributed singularities. This phenomenon is verified experimentally through the infrared spectral measurement. Our work provides the possibility to produce integrated light-harvesting devices for numerous optical applications in illumination, display, and enhanced nonlinear excitation.