Optical skyrmion lattice in evanescent electromagnetic fields

TLDR

Topological defects, including skyrmions, are pivotal across many physical systems and hold promise for magnetic storage and spintronics. The study demonstrates that optical skyrmion lattices can be readily created and controlled, and shows their robustness to imperfections. Optical skyrmions were generated by interfering surface plasmon polaritons and characterized with phase‑resolved near‑field optical microscopy. This discovery opens new photonic phenomena, enables light‑induced skyrmion generation in materials, and offers applications in optical information processing, transfer, and storage.

Abstract

Topological defects play a key role in a variety of physical systems, ranging from high-energy to solid state physics. They yield fascinating emergent phenomena and serve as a bridge between the microspic and macroscopic world. A skyrmion is a unique type of topological defect, showing great promise for applications in the fields of magnetic storage and spintronics. Here, we discover and observe optical skyrmion lattices that can be easily created and controlled, while illustrating their robustness to imperfections. Optical skyrmions are experimentally demonstrated by interfering surface plasmon polaritons and are measured via phase-resolved near-field optical microscopy. This discovery could give rise to new physical phenomena involving skyrmions and exclusive to photonic systems; open up new possibilities for inducing skyrmions in material systems through light-matter interactions; and enable applications in optical information processing, transfer and storage.