  Micromagnetic simulations have been performed to investigate the suppression
of the skyrmion Hall effect in nanotracks with their magnetic properties
strategically modified. In particular, we study two categories of magnetically
modified nanotracks. One of them, repulsive edges have been inserted in the
nanotrack and, in the other, an attractive strip has been placed exactly on the
longest axis of the nanotrack. Attractive and repulsive interactions can be
generated from the engineering of magnetic properties. For instance, it is
known that the skyrmion can be attracted to a region where the exchange
stiffness constant is decreased. On the other hand, the skyrmion can be
repelled from a region characterized by a local increase in the exchange
stiffness constant. In order to provide a background for experimental studies,
we vary not only the magnetic material parameters (exchange stiffness,
perpendicular magnetocrystalline anisotropy and the Dzyaloshinskii-Moriya
constant) but also the width of the region magnetically modified, containing
either a local reduction or a local increase for each one of these magnetic
properties. In the numerical simulations, the skyrmion motion was induced by a
spin-polarized current and the found results indicate that it is possible to
transport skyrmions around the longest axis of the nanotrack. In practice, the
skyrmion Hall effect can be completely suppressed in magnetic nanotracks with
strategically modified magnetic properties. Furthermore, we discuss in detail 6
ways to suppress the skyrmion Hall effect by the usage of nanotracks with
repulsive edges and nanotracks with an attractive strip.
