Science 361, 993–996 (2018)

Best thought of as topological excitations that share the same topology as a set of magnetic moments wrapped around a sphere, skyrmions are widely thought to be promising for magnetic storage and spintronics applications. Shai Tsesses and colleagues have now brought skyrmions into the arena of optics. By controlling the interference of plasmon polaritons on a patterned metallic surface, they have succeeded in creating a lattice of optical skyrmions. The authors were able to image this pattern of evanescent electromagnetic fields using a phase-resolved near-field optical microscope.

In contrast to their magnetic analogues studied in solid-state systems, these optical skyrmions can be continuously tuned from a so-called bubble- to Néel-type structure. However, in common with many such topological excitations, the lattice of optical skyrmions displays a remarkable robustness to imperfections. The extent to which light can be manipulated and processed in photonic systems has already given us countess technologies. Few would bet against a few more popping out following this discovery of photonic skyrmions.