Bloch-type photonic skyrmions in optical chiral multilayers

TL;DR

This paper predicts and demonstrates the existence of Bloch-type photonic skyrmions in chiral multilayered structures, expanding the family of photonic skyrmions and highlighting their potential in advanced optical technologies.

Contribution

It introduces the first theoretical prediction of Bloch-type photonic skyrmions in chiral multilayers using the quantum spin Hall effect of plasmonic vortices.

Findings

Prediction of Bloch- and Ne9el-type skyrmions in optical structures

Chirality-dependent features enable new sensing and data storage options

Reveals similarities between photonic and magnetic skyrmions

Abstract

Magnetic skyrmions are topological quasiparticles in magnetic field. Until recently, as one of their photonic counterparts, N\'eel-type photonic skyrmion is discovered in surface plasmon polaritons. The deep-subwavelength features of the photonic skyrmions suggest their potentials in quantum technologies and data storage. So far, the Bloch-type photonic skyrmion has yet to be demonstrated in this brand new research field. Here, by exploiting the quantum spin Hall effect of a plasmonic optical vortex in multilayered structure, we predict the existence of photonic twisted-N\'eel- and Bloch-type skyrmions in chiral materials. Their chirality-dependent features can be considered as additional degrees-of-freedom for future chiral sensing, information processing and storage technologies. In particular, our findings enlarge the family of photonic skyrmions and reveal a remarkable resemblance of the feature of chiral materials in two seemingly distant fields: photonic skyrmions and magnetic skyrmions.