Field-Dependent Size and Shape of Single Magnetic Skyrmions

TL;DR

This study investigates the size and shape variations of individual magnetic skyrmions in ultrathin films using spin-polarized STM, revealing their field-dependent properties and linking experimental data to theoretical models.

Contribution

It provides a detailed real-space analysis of skyrmion structures and introduces an analytical expression connecting experimental observations with theoretical descriptions.

Findings

Skyrmion size and shape depend on magnetic field.

Atomic-scale spin structures are characterized with spin-polarized STM.

Material parameters for skyrmion formation are extracted.

Abstract

The atomic-scale spin structure of individual isolated skyrmions in an ultrathin film is investigated in real space by spin-polarized scanning tunneling microscopy. Their axial symmetry as well as their unique rotational sense is revealed by using both out-of-plane and in-plane sensitive tips. The size and shape of skyrmions change as a function of magnetic field. An analytical expression for the description of skyrmions is proposed and applied to connect the experimental data to the original theoretical model describing chiral skyrmions. Thereby, the relevant material parameters responsible for skyrmion formation can be obtained.