Domain wall-gated skyrmion logic

TL;DR

This paper demonstrates how domain walls can control skyrmion transport in magnetic racetracks, enabling the construction of logic gates like NOT, NAND, and NOR for skyrmion-based computing.

Contribution

It introduces a novel domain wall-gated skyrmion logic architecture using numerical simulations of skyrmion-domain wall collisions in a racetrack.

Findings

Domain wall modulation can control skyrmion transport.

Logical gates can be realized via domain wall configurations.

The system is compatible with racetrack memory technology.

Abstract

Skyrmions and domain walls are typical spin textures of significant technological relevance to magnetic memory and logic applications, where they are used as carriers of information. The unique topology of skyrmions makes them to display distinct dynamical properties compared to domain walls. Some studies have demonstrated that the two topologically inequivalent magnetic objects could be interconverted by cleverly designed geometric structures. Here, we numerically address the skyrmion-domain wall collision in a magnetic racetrack by introducing relative motion between the two objects based on a specially designed junction. An electric current serves as the driving force that moves a skyrmion toward a trapped domain-wall pair. We observe different types of collision dynamics by changing the driving parameters. Most importantly, the domain wall modulation of skyrmion transport is realized in this system, allowing a set of domain wall-gated logical NOT, NAND, and NOR gates to be constructed. By providing a promising logic architecture that is fully compatible with racetrack memories, this work is expected to speed up the development of skyrmion-based magnetic computation.