  Magnetic skyrmions are particle-like topological excitations recently
discovered in chiral magnets. Their small size, topological protection and the
ease with which they can be manipulated by electric currents generated much
interest in using skyrmions for information storage and processing. Recently,
it was suggested that skyrmions with additional degrees of freedom can exist in
magnetically frustrated materials. Here, we show that dynamics of skyrmions and
antiskyrmions in nanostripes of frustrated magnets is strongly affected by
complex spin states formed at the stripe edges. These states create multiple
edge channels which guide the skyrmion motion. Non-trivial topology of edge
states gives rise to complex current-induced dynamics, such as emission of
skyrmion-antiskyrmion pairs. The edge state topology can be controlled with an
electric current through the exchange of skyrmions and antiskyrmions between
the edges of a magnetic nanostructure. These results can lead to conceptually
new electronic devices.
