ExMAM · Excitonic 2D Metasurfaces for Active Multifunctional Flat Optics

Can light fields be manipulated by a single atomic layer? Can quantum mechanical effects in monolayer materials be harnessed to realize dynamic optical elements? Recent work has demonstrated that light-weight and ultra-thin nanostructured optical coatings (metasurfaces) can perform the same optical functions as conventional bulky optical components. Despite these advances, metasurface optical elements have remained static. At the same time, newly emerging and future applications require optical elements with dynamic control of their functionality.Here, I propose to lay the foundations of a completely new class of tunable and multifunctional optical elements by combining recent developments in 2D material science, quantum physics, and nanophotonics, resulting in highly novel excitonic 2D metasurfaces. Building on my strong expertise in the fields of optical metasurfaces and 2D material physics, I will employ monolayer 2D quantum materials to actively tune the optical response of novel nonlocal metasurfaces. These atomically-thin materials exhibit a strong quantum-mechanical exciton resonance in the visible spectral range, even at room temperature. Using electrical control over this exciton resonance, I will study the interplay of localized excitons and delocalized optical modes. Next, I will realize ultracompact optical elements with electrically-tunable functionality. Finally, I will develop novel methods to combine stacked metasurfaces in compound meta-optics that offer multifunctional dynamic optical components.The excitonic 2D metasurfaces open new routes to study the unconventional properties of quantum materials in quantum optics, nanophotonics, and solid-state physics. At the same time, the results of this project open an entirely new approach for the design of actively-tunable multifunctional flat optical components with applications in optical communication, augmented reality, and computational imaging.