Shai Tsesses

Optical skyrmion lattice in evanescent electromagnetic fields

Generating a lattice of optical skyrmions The topological properties of systems can be robust to defects and imperfections. Skyrmions are one such topological entity, which resemble “hedgehog-like” structures. Tsesses et al. controlled the interference of plasmon polaritons on a patterned metallic surface to generate a lattice of optical skyrmions. Such control could potentially optically mimic complex condensed matter systems or help in the development of robust optical communications and circuits. Science, this issue p. 993 Controlled interference of surface plasmons can result in the generation of optical skyrmions. Topological defects play a key role in a variety of physical systems, ranging from high-energy to solid-state physics. A skyrmion is a type of topological defect that has shown promise for applications in the fields of magnetic storage and spintronics. We show that optical skyrmion lattices can be generated using evanescent electromagnetic fields and demonstrate this using surface plasmon polaritons, imaged by phase-resolved near-field optical microscopy. We show how the optical skyrmion lattice exhibits robustness to imperfections while the topological domain walls in the lattice can be continuously tuned, changing the spatial structure of the skyrmions from bubble type to Néel type. Extending the generation of skyrmions to photonic systems provides various possibilities for applications in optical information processing, transfer, and storage.