Dynamics of distorted skyrmions in strained chiral magnets

Abstract

In this work, we study the microscopic dynamics of distorted skyrmions in strained chiral magnets (Shibatak et al 2015 Nat. Nanotechnol. 10 589) under gradient magnetic field and electric current by Landau-Lifshitz-Gilbert simulations of the anisotropic spin model. It is observed that the dynamical responses are also anisotropic, and the velocity of the distorted skyrmion is periodically dependent on the directions of the external stimuli. Furthermore, in addition to the uniform motion, our work also demonstrates an anti-phase harmonic vibration of the two skyrmions in nanostripes, and the frequencies can be effectively modulated by the anisotropic Dzyaloshinskii-Moriya interaction. The simulated results are well explained by Thiele's theory, which may provide useful information in understanding the dynamics of the distorted skyrmions.

Controlling the helicity of magnetic skyrmions by electrical field in frustrated magnets

“…It has been widely confirmed that these skyrmions are primarily induced by the Dzyaloshinskii-Moriya interaction (DMI), stemming from inversion-symmetry-breaking and the spin-orbit interaction of different kinds. For example, Bloch-type skyrmions can be stabilized in chiral magnets with the Dresselhaus spin-orbit interaction, while Néel-type skyrmions may appear in polar magnets with the Rashba spin-orbit interaction or in magnetic ultrathin films with interfacial DMI [30][31][32][33]. Meanwhile, the magnetic antiskyrmions discovered in Heusler compounds are stabilized by the anisotropic DMI with opposite signs along two orthogonal in-plane directions [34][35][36][37][38].…”

Enhanced Stability of Antiferromagnetic Skyrmion during Its Motion by Anisotropic Dzyaloshinskii–Moriya Interaction

“…As a matter of fact, similar phenomenon has been observed in the motion of the distorted ferromagnetic skyrmion driven by the in-plane current. 30 Furthermore, the anisotropic dynamical responses of the ferromagnetic skyrmion has been reported, and similar behavior could be also existed in AFM system, which deserves to be further checked.…”

“…It is revealed in our earlier work that the anisotropic DM interaction in strained FeGe plays an essential role in the skyrmion deformation, and results in an anisotropic dynamics of the distorted skyrmion. [30] Most recently, strong DM interaction anisotropy induced by compressive strain was also reported in Co/Pt multilayers. [31] In some extent, DM interaction anisotropy could be also induced by applying uniaxial or anisotropic strain in AFM film, and results in a deformation of AFM skyrmion.…”

Spin waves in skyrmionic structures with various topological charges

“…It has been shown recently that such distorted spin configurations are also stable in chiral magnets in the absence of frustrated isotropic interactions [40]. The asymmetric shape and the alignment of the skyrmionic structures along preferential directions on the lattice has been demonstrated to have a profound effect on their current-driven dynamics [41,42,43] and thermal diffusion [44].…”