Thermal stability and topological protection of skyrmions in nanotracks

David Cortés-Ortuño, Weiwei Wang, Marijan Beg, Ryan A. Pepper, Marc-Antonio Bisotti, Rebecca Carey, Mark Vousden, Thomas Kluyver, Ondrej Hovorka, Hans Fangohr

Published 2016-11-21Version 1

Magnetic skyrmions are hailed as a potential technology for data storage and other data processing devices. However, their stability against thermal fluctuations is an open question that must be answered before skyrmion-based devices can be designed. In this work, we study paths in the energy landscape via which the transition between the skyrmion and the uniform state can occur in interfacial Dzyaloshinskii-Moriya finite-sized systems. We find three mechanisms the system can take in the process of skyrmion nucleation or destruction and identify that the transition facilitated by the boundary has a significantly lower energy barrier than the other energy paths. This clearly demonstrates the lack of the skyrmion topological protection in finite-sized magnetic systems. Overall, the energy barriers of the system under investigation are too small for storage applications at room temperature, but research into device materials, geometry and design may be able to address this.