Voltage Controlled Magnetic Skyrmion Motion for Racetrack Memory

TL;DR

This paper explores voltage-controlled magnetic anisotropy to manipulate skyrmion pinning and depinning in racetrack memory, providing a compact model and bridging physics with electronic design for practical applications.

Contribution

It introduces a voltage-controlled approach to skyrmion pinning/depinning and proposes a compact model for electrical evaluation of skyrmion-based racetrack memory.

Findings

Demonstrated voltage-controlled pinning/depinning of skyrmions.

Developed a compact model for skyrmion behavior.

Bridged physics and electronic design for memory applications.

Abstract

Magnetic skyrmion, vortex-like swirling topologically stable spin configurations, is appealing as information carrier for future nanoelectronics, owing to the stability, small size and extremely low driving current density. One of the most promising applications of skyrmion is to build racetrack memory (RM). Compared to domain wall-based RM (DW-RM), skyrmion-based RM (Sky-RM) possesses quite a few benefits in terms of energy, density and speed etc. Until now, the fundamental behaviors, including nucleation/annihilation, motion and detection of skyrmion have been intensively investigated. However, one indispensable function, i.e., pinning/depinning of skyrmion still remains an open question and has to be addressed before applying skyrmion for RM. Furthermore, Current research mainly focuses on physical investigations, whereas the electrical design and evaluation are still lacking. In this work, we aim to promote the development of Sky-RM from fundamental physics to realistic electronics. First, we investigate the pinning/depinning characteristics of skyrmion in a nanotrack with the voltage-controlled magnetic anisotropy (VCMA) effect. Then, we propose a compact model and design framework of Sky-RM for electrical evaluation. This work completes the elementary memory functionality of Sky-RM and fills the technical gap between the physicists and electronic engineers, making a significant step forward for the development of Sky-RM.