# Skyrmion dynamics in a frustrated ferromagnetic film and current-induced helicity locking-unlocking transition

## TL;DR

This paper investigates the behavior of skyrmions in frustrated magnetic materials, revealing how current influences their helicity and motion, and demonstrating phenomena like bound states and annihilation, with implications for topological magnetism applications.

## Contribution

It introduces a detailed model of skyrmion dynamics in frustrated magnets, highlighting helicity locking-unlocking transitions and bound state formation due to dipole interactions.

## Key findings

- Helicity-dependent energy leads to fixed-helicity translational motion.
- Current induces a transition from helicity locking to unlocking, changing skyrmion motion.
- Spontaneous formation and current-driven separation of skyrmion bound states.

## Abstract

The helicity-orbital coupling is an intriguing feature of magnetic skyrmions in frustrated magnets. Here, we explore the skyrmion dynamics in a frustrated magnet based on the $J_{1}$-$J_{2}$-$J_{3}$ classical Heisenberg model explicitly by including the dipole-dipole interaction. The skyrmion energy acquires a helicity dependence due to the dipole-dipole interaction, resulting in the current-induced translational motion with a fixed helicity. The lowest energy states are the degenerate Bloch-type states, which can be used for building the binary memory. By increasing the driving current, the helicity locking-unlocking transition occurs, where the translational motion changes to the rotational motion. Furthermore, we demonstrate that two skyrmions can spontaneously form a bound state. The separation of the bound state forced by a driving current is also studied. In addition, we show the annihilation of a pair of skyrmion and antiskyrmion. Our results reveal the distinctive frustrated skyrmions may enable viable applications in topological magnetism.