Symmetry breaking in spin spirals and skyrmions by in-plane and canted magnetic fields

TL;DR

This study investigates how in-plane and canted magnetic fields influence the behavior and shape of spin spirals and skyrmions in atomic bilayer islands, revealing their cycloidal nature and magnetization rotation sense.

Contribution

It demonstrates the reorientation and distortion of spin spirals and skyrmions under magnetic fields, providing experimental evidence for their cycloidal nature and Dzyaloshinskii-Moriya interaction effects.

Findings

Spin spiral propagation is determined by island borders.

In-plane fields reorient and distort spin spirals.

Canted fields distort skyrmion shapes, revealing magnetization rotation.

Abstract

The influence of in-plane and canted magnetic fields on spin spirals and skyrmions in atomic bilayer islands of palladium and iron on an Ir(111) substrate is investigated by scanning tunnelling microscopy at low temperatures. It is shown that the spin spiral propagation direction is determined by the island's border which can be explained by equilibrium state calculations on a triangular lattice. By application of in-plane fields, the spin spiral reorientates its propagation direction and becomes distorted, thereby allowing a proof for its cycloidal nature. Furthermore, it is demonstrated that the skyrmions' shape is distorted in canted fields which allows to determine the sense of magnetisation rotation as enforced by the interfacial Dzyaloshinskii-Moriya interaction.