Review: Interface nano-optics with van der Waals polaritons
An international team, including the leader of the Nanooptics group at nanoGUNE, Rainer Hillenbrand, discusses in ‘Nature’ the state-of-the-art and opportunities for controlling the propagation of nanolight (in form of polaritons) in van der Waals materials with the help of classical refractive optics concepts, meta-optics and moire engineering.
Polaritons are hybrid excitations of matter and photons. In recent years, polaritons in van der Waals nanomaterials—known as van der Waals polaritons—have shown great promise to guide the flow of light at the nanoscale over spectral regions ranging from the visible to the terahertz. A vibrant research field based on manipulating strong light–matter interactions in the form of polaritons, supported by these atomically thin van der Waals nanomaterials, is emerging for advanced nanophotonic and opto-electronic applications.
In this review article the international team provide an overview of the state of the art of exploiting interface optics—such as refractive optics, meta-optics and moiré engineering—for the control of van der Waals polaritons. This enhanced control over van der Waals polaritons at the nanoscale has not only unveiled many new phenomena, but has also inspired valuable applications—including new avenues for nano-imaging, sensing, on-chip optical circuitry, and potentially many others in the years to come.