Structuring light with optical metasurfaces

Metasurfaces are planar metamaterials consisting of nanostructures that allow to manipulate the phase, amplitude and polarization of light on a subwavelength scale with unprecedented control, representing the state-of-the-art in structured light.

This nanotechnology is not anymore, an academic curiosity: today metasurfaces are being mass produced and can be fabricated with large areas (10 cm) using advanced lithography techniques. These meta-optics are pushing the boundaries of structured light, allowing to exploit all of its degrees of freedom, even creating correlations between these resulting in complex multimodal forms of light, such as space-time beams. In this contribution we will discuss the most recent advances in the field and where the most exciting opportunities lie ahead, in particular in the areas of nonlinear optical neural networks and structured laser-matter interactions.