Fig. 2. Metafiber design for generating tunable optical skyrmions.

a Ideal and simulated light field distributions of the skyrmion with components J₀ and J₁ in orthogonal linear polarizations. The first and second columns are ideal profiles and the third and fourth are simulated profiles. The intensity profiles in the longitudinal plane $xz\left(y=0\right)$, and the intensity and phase profiles in the transverse $xy$ plane (with $z$ marked by white lines in the first-row figures) are illustrated from top to bottom. b The manipulation of skyrmion/non-skyrmion states via input polarization angle $\theta$. The vector distributions of major states are shown. c Normalized power curves with respect to the polarization angle. The intensity profiles of J₀ and J₁ of different polarization angles are inserted and marked in lines with dots. a.u.: arb. units. d The manipulation of topological transformation between different quasiparticles via quarter wave plate. e The maps on the Poincaré sphere in the transformation between skyrmion and non-skyrmion states in different polarization angles $\theta$ in simulation, with the corresponding skyrmion numbers N_sk.