Broadband Forward Light Scattering by Architectural Design of Core–Shell Silicon Particles

A goal in the field of nanoscale optics is fabrication nanostructures with strong directional light scattering at visible frequencies. Here, synthesis Mie-resonant core–shell particles overlapping electric and magnetic dipole resonances spectrum demonstrated. The core consists silicon surrounded by a lower index oxynitride (SiOxNy) shell an adjustable thickness. Optical spectroscopies coupled to Mie theory calculations give first experimental evidence that relative position intensity are tuned changing architecture. Specifically, coating high-index particle low-index coalesces dipoles, while maintaining high efficiency, thus generating broadband forward scattering. This synthetic strategy opens route toward metamaterial unprecedented control over manipulation.