Topological Approach of Characterizing Optical Skyrmions and Multi‐Skyrmions

Abstract

Abstract The skyrmion number of paraxial optical skyrmions can be defined solely via their polarization singularities and associated winding numbers, using a mathematical derivation that exploits Stokes's theorem. It is demonstrated that this definition provides a robust way to extract the skyrmion number from experimental data, as illustrated for a variety of optical (Néel‐type) skyrmions and bimerons and multi‐skyrmions. This method generates not only an increase in accuracy, but also provides an intuitive geometrical approach to understanding the topology of such quasi‐particles of light and their robustness against smooth transformations.