We introduce a family of models for magnetic skyrmions in the plane for which infinitely many solutions can be given explicitly. The energy defining the models is bounded below by a linear combination of degree and total vortex strength, and the configurations attaining the bound satisfy a first order Bogomol'nyi equation. We give explicit solutions which depend on an arbitrary holomorphic function. The simplest solutions are the basic Bloch and Néel skyrmions, but we also exhibit distorted and rotated single skyrmions as well as line defects, and configurations consisting of skyrmions and anti-skyrmions. arXiv:1812.07268v2 [cond-mat.str-el]

We exhibit a close relation between vortex configurations on the 2-sphere and magnetic zero-modes of the Dirac operator on which obey an additional nonlinear equation. We show that both are best understood in terms of the geometry induced on the 3-sphere via pull-back of the round geometry with bundle maps of the Hopf fibration. We use this viewpoint to deduce a manifestly smooth formula for square-integrable magnetic zero-modes in terms of two homogeneous polynomials in two complex variables.

Starting from the geometrical interpretation of integrable vortices on twodimensional hyperbolic space as conical singularities, we explain how this picture can be expressed in the language of Cartan connections, and how it can be lifted to the double cover of three-dimensional Anti-de Sitter space viewed as a trivial circle bundle over hyperbolic space. We show that vortex configurations on the double cover of AdS space give rise to solutions of the Dirac equation minimally coupled to the magnetic field of the vortex. After stereographic projection to (2+1)-dimensional Minkowski space we obtain, from each lifted hyperbolic vortex, a Dirac field and an abelian gauge field which solve a Lorentzian, (2+1)-dimensional version of the Seiberg-Witten equations.

A simple mathematical expression based on rational maps to describe all optical paraxial skyrmion known to date, including Néel‐type and Bloch‐type skyrmions, bimerons, and anti‐skyrmions, is introduced. This expression is derived solely from topological considerations and outlines the rules that fully polarized paraxial light fields must obey to qualify as optical skyrmions. It is shown that rational maps can be implemented experimentally by superposing a pair of orthogonally polarized Laguerre–Gaussian modes. Novel optical skyrmion fields, called multi‐skyrmions, are obtained upon generalizing the proposed expression, laying the foundation for the exploration of skyrmion nucleation and annihilation mechanisms in optics.