Chapter 8 Magnetic Skyrmion Dynamics

Abstract

In this chapter, the dynamics of magnetic skyrmions is reviewed. Starting with a topological definition of what we call a magnetic skyrmion, we describe the topology and discuss the resulting general properties. To stabilize chiral skyrmions, we introduce a chiral exchange interaction and we present the spin canting that leads to a given handedness for chiral skyrmions. Based on the statics, we next describe the dynamics based on a one-dimensional model and then discuss the steady-state dynamics for instance in wire geometries as well as the gyrotropic relaxation eigenmodes. Finally, we present an experimental demonstration of both these types of dynamics and give a brief outlook on future challenges and opportunities in this field.

Topological Structures in Ferroic Materials

“…a transverse current. This is detected as an additional component to the Hall voltage of the system, the so-called topological Hall effect (THE) [47]. The THE can be used to identify the presence of topologically stable ordering in a magnetic system.…”

Nanosecond X-Ray Photon Correlation Spectroscopy on Magnetic Skyrmions

“…The quasiparticle equation of motion used for gyrotropic eigenmodes is most likely not applicable here since the rotational motion of these objects in the plane of the sample, perpendicular to the x-ray propagation vector, would not contribute to a decay in contrast of the speckle patterns [52]. It is clear that spin fluctuations, random motion, and lateral fluctuations of domain walls all contribute, and will be the focus for this method in the future, both from an experimental and a theoretical perspective.…”