Axial optical polarization skyrmion array within tightly focused fields by inversion of dipole antenna radiation

Abstract

Optical skyrmions have gained considerable interest for their robust electromagnetic field configurations. In this study, we demonstrate a novel method to generate axial optical polarization skyrmion structure, including continuous optical skyrmion structure in needle field (8λ) and discrete optical skyrmion array in multifocal field. By combining time-reversal dipole array radiation with vectorial tight-focusing techniques, we achieve controlled formation of both Néel-type and Bloch-type skyrmions. The spatial evolution of the topological structure within the axial optical needle field is examined, and the polarity of the optical skyrmion is periodically modulated by the axial electric field E_z. In the multifocal field, by introducing time-reversal magnetic dipole radiation, we achieve precise control over the skyrmion structures at any pair of focal points, thereby realizing the transformation from Néel-type to Bloch-type configurations. This work providing a theoretical foundation and contributes to the development of methods for constructing and regulating optical topological structures.