Generation and annihilation of skyrmions and antiskyrmions in magnetic heterostructures

We demonstrate the controlled generation and annihilation of (anti)skyrmions with tunable chirality in magnetic heterostructures by means of micromagnetic simulations. By making use of magnetic (anti)vortices in a patterned ferromagnetic layer, we stabilize (anti)skyrmions in an underlying skyrmionic thin film in a reproducible manner. The stability of the (anti)skyrmion depends on the polarization of the (anti)vortex, whereas their chirality is given by those of the (anti)vortices. We investigate the influence of geometric parameters such as nanodisk radius and film thickness on the stability of the (anti)skyrmions. By introducing the interlayer Dzyaloshinskii-Moriya interaction into our modeling, we predict that the same coupling mechanism works also for chiral skyrmions. Furthermore, we demonstrate that the core coupling between the (anti)vortices and (anti)skyrmions allows deleting and writing of spin objects in a controlled fashion by applying short pulses of in-plane external magnetic fields or charge currents, representing a new key paradigm in skyrmionic devices.