Turning a chiral skyrmion inside out

The stability of two-dimensional chiral skyrmions in a tilted magnetic field is studied. It is shown that by changing the direction and magnitude of the field, one can continuously transform a chiral skyrmion into a skyrmion with opposite polarity and vorticity. This turned inside out skyrmion can be considered as an antiparticle for an ordinary axisymmetric skyrmion. For any tilt angle of the magnetic field, there is a range of its absolute values where two types of skyrmions may coexist. In a tilted field the potentials for interskyrmion interactions are characterized by the presence of local minima suggesting an attractive interaction between the particles. The potentials of interparticle interactions also have so-called fusion channels allowing either the annihilation of two particles or the emergence of a another particle. The presented results are general for a wide class of magnetic crystals with both easy-plane and easy-axis anisotropies.