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Topological spin textures on artificial pinning landscape may show unique static and dynamic properties. Here, we computationally show that the helicity of frustrated skyrmions on an artificial square-grid obstacle pattern can be switched by a spin current pulse. The obstacle pattern is formed by defect lines with enhanced perpendicular magnetic anisotropy, which could protect the skyrmion from being annihilated at the sample edge. It is found that the skyrmion driven by a moderate current shows a circular motion guided by the boundary of the obstacle pattern, while it shows an almost straight motion toward the sample edge in the absence of the obstacle pattern. By applying a short pulse current to drive the skyrmion in a sample with the obstacle pattern, we find that the helicity of the skyrmion could be switched between Bloch-type configurations favored by the dipole-dipole interaction. Besides, we demonstrate the possibility of switching the helicity of an array of skyrmions on the square-grid obstacle pattern using the same method. Our results could be useful for the helicity control of topological spin textures, and may provide guidelines for building future helicity-based spintronic functions.

Editorial on the Research Topic Generation, Detection and Manipulation of Skyrmions in Magnetic NanostructuresWith the rapid accumulation of data in science, technology, and social activity in the development of modern society, it is becoming increasingly urgent and important to find efficient and effective methods to store and process information with low power consumption. The skyrmion, a curling field configuration, was originally proposed by nuclear physicist Skyrme [1] and it was recently realized in a wide class of magnetic materials with chiral exchange interactions [2][3][4]. Due to their compact shape and small size down to a few nanometers, good thermal stability, and low driven current density, magnetic skyrmions have become promising building blocks for high-density storage and fast information processing applications. In a dozen years, this field dubbed as skyrmionics has attracted significant attention for exploring fundamental physics as well as for practical applications.This research topic entitled "Generation, Detection, and Manipulation of Skyrmions in Magnetic Nanostructures" aims to address the recent developments in the field of skyrmionics. Particularly, the featured topics include the interplay of skyrmions and spin waves, pinning effects of disorder and defects on skyrmion motion, and the design of spintronic devices with information encoded in skyrmions and other magnetic solitons.Two articles present the interplay of spin waves and magnetic skyrmions. Guan et al. show that an antiferromagnetic skyrmion driven by double circularly-polarized spin waves could move along the intersection of the two microwave sources. Here the skyrmion Hall effect is strongly suppressed because the effective transverse forces acting on the skyrmions generated by the left-handed and right-handed spin waves cancel each other. This theoretical proposal may help to guide skyrmion motion in a desirable trajectory. Yao et al. considered skyrmion generation by spin waves reflected from a curved surface. Usually, spin-wave energy is too small to overcome the barrier between a skyrmion and a ferromagnetic state. Here the authors carefully design a parabolic film edge such that the intensity of spin waves totally reflected from the edge is