Cooperative Charge Pumping and Enhanced Skyrmion Mobility

TL;DR

This paper explores how moving skyrmions can generate charge currents through their magnetic topology, with potential applications in racetrack memory devices.

Contribution

It introduces a theoretical framework linking skyrmion motion to charge pumping, highlighting the role of topology and scattering effects.

Findings

Skyrmion motion induces significant charge currents.

Charge pumping scales with electron reflection coefficient.

Potential for enhanced skyrmion mobility in racetrack devices.

Abstract

The electronic pumping arising from the steady motion of ferromagnetic skyrmions is investigated by solving the time evolution of the Schrodinger equation implemented on a tight-binding model with the statistical physics of the many-body problem. It is shown that the ability of steadily moving skyrmions to pump large charge currents arises from their non-trivial magnetic topology, i.e. the coexistence between spin-motive force and topological Hall effect. Based on an adiabatic scattering theory, we compute the pumped current and demonstrate that it scales with the reflection coefficient of the conduction electrons against the skyrmion. Finally, we propose that such a phenomenon can be exploited in the context of racetrack devices, where the electronic pumping enhances the collective motion of the train of skyrmions.