Dynamic motion of polar skyrmions in oxide heterostructures

TL;DR

This paper demonstrates the external stimuli-driven dynamic motion of polar skyrmions in oxide heterostructures using phase-field simulations, revealing how thermal, electrical, and mechanical forces influence skyrmion behavior and offering guidance for device design.

Contribution

It introduces the first simulation-based demonstration of external field-driven polar skyrmion motion and explores how various stimuli affect their dynamics and interactions.

Findings

Heating reduces polarization and skyrmion motion barriers.

Electric fields cause skyrmion shrinking and weaken lattice pinning.

Mechanical force transforms skyrmions into c-domains near the indenter.

Abstract

Polar skyrmions have been widely investigated in oxide heterostructure recently, due to their exotic properties and intriguing physical insights. Meanwhile, so far, the external field-driven motion of the polar skyrmion, akin to the magnetic counterpart, has yet to be discovered. Here, using phase-field simulations, we demonstrate the dynamic motion of the polar skyrmions with integrated external thermal, electrical, and mechanical stimuli. The external heating reduces the spontaneous polarization hence the skyrmion motion barrier, while the skyrmions shrink under the electric field, which could weaken the lattice pinning and interactions between the skyrmions. The mechanical force transforms the skyrmions into c-domain in the vicinity of the indenter center under the electric field, providing the space and driving force needed for the skyrmions to move. This study confirmed that the skyrmions are quasi-particles that can move collectively, while also providing concrete guidance for the further design of polar skyrmion-based electronic devices.