The hidden light of quantum matter

The past decade has seen a rapid growth of research on topological quantum matter, while at the same time topological photonics has witnessed an explosion, mainly focused on artificially structured media like photonic crystals and meta-materials. Considering that light and dipolar matter excitations can strongly interact to form hybridized modes, so-called polaritons, this naturally leads to an intriguing question: Can atomic crystals, without the need for any macroscopic engineering, host electromagnetic topological states that are fundamentally distinct from their frequently explored fermionic counterparts? That is, are there intrinsically bosonic electromagnetic quantum phases, and if so, what are their physical observables?

Since from a theoretical perspective, the first part of the last question has recently been answered positively, the goal of this PhD research project will be to experimentally explore topological electromagnetic states of quantum matter based on the development of new scanning probe techniques. Leveraging our new cryogenic high-magnetic field scanning probe microscope you will try to ‘feel’ the topology of electromagnetic near-fields via photo-induced force modulations, and demonstrate the real-space imaging of polaritonic textures in the electromagnetic near-fields of viscous Hall fluids, semimetals, and superconductors.