  In this paper we investigate a magnetic racetrack consisting of a junction of
three materials with different properties. Indeed, this magnetic system is
composed by two distinct regions (racetracks) connected by a thin interface:
the first region (termed sector $1$) has isotropic in-plane magnetic chirality
and supports skyrmion ($S$) excitations while the second (sector $3$) has
anisotropic chirality and consequently supports antiskyrmions ($A$). The
interface, which would be a third region (sector $2$, connecting sectors $1$
and $3$) located in the central part of the racetrack, is an easy-axis
Heisenberg ferromagnetic material. The topological structures $S$ and $A$ are
put in motion by applying a spin-polarized current. Under certain conditions,
we show that the skyrmion and the antiskyrmion created in their respective
sectors are simultaneously impelled to the interface (due to the Magnus force)
to apparently become a unique object (a skyrmion-antiskyrmion pair or $SAP$).
After glued by sector $2$, the skyrmion and the antiskyrmion move together (as
a $SAP$) along the direction of the applied current. It is also shown that such
an engineered racetrack can support a sequence of several $SAP$ structures in
motion, forming a current.
