Manipulating light at the nanoscale: from optical antennas to metasurfaces

 Antenna resonators are at the heart of modern radio and microwave frequency communications technologies. Antenna concepts have been recently extended to the infrared and optical frequency domains, greatly enhancing light-matter interactions in a variety of nanophotonic systems and eventually launching the field of metasurfaces ─ the optical frequency analogs of phased array radar. This ability to manipulate light at subwavelength scales have led to numerous demonstrations of flat optical elements including, lenses, beam deflectors , holograms, light sources etc. In this talk, I discuss the rich optical response of dielectric antenna resonators arising from multipolar Mie resonances. I demonstrate bottom-up techniques for fabricating nanoparticles and metasurfaces with controlled size and shape and the ability to engineer their response across the visible to mid-infrared spectral ranges. I show how the wealth of electric and magnetic resonances in these nanostructures can be exploited to manipulate both classical and quantum properties of light. I will also present various materials and approaches for dynamic control of light such as phase-change materials, semiconductors and topological insulators.