Prof. Dr. Carsten Ronning
Friedrich-Schiller-Universität Jena

Ion beam designed metasurfaces

Carsten Ronning

Institut für Festkörperphysik, Friedrich-Schiller-Universität Jena

Merging industrial relevant ion beam technologies and the emerging science of ultra-thin active metasurfaces holds tremendous potential for the creation of large-scale, dynamically controlled optical meta-devices, and is a decisive step towards inherently planar optics. Novel metasurfaces for a broad and tunable spectral range can be designed by selective engineering of the refractive indices of thin dielectric films making use of ion beam irradiation through subwavelength-patterned masks or direct writing by a focused ion beam. The relevant dielectric material systems, which are used to create the metasurfaces - phase change materials, phase transition materials, silicon - offer low optical losses and possible dynamic control of their optical properties by an external stimulus. In this colloquium, I will show three examples based on ion irradiated VO₂, Ge₂Sb₂Te₅ and silicon.