# Electrical writing, deleting, reading, and moving of magnetic skyrmioniums in a racetrack device

## TL;DR

This paper introduces a novel optoelectrical method for writing, deleting, reading, and moving magnetic skyrmioniums in racetrack devices, highlighting their advantages over skyrmions for information storage.

## Contribution

It proposes new mechanisms for skyrmionium manipulation and demonstrates their potential as reliable information carriers in racetrack memory devices.

## Key findings

- Successful simulation of creation, motion, detection, and deletion of skyrmioniums.
- Skyrmioniums offer advantages over skyrmions in current-driven motion.
- Topological Hall voltage enables effective reading of skyrmioniums.

## Abstract

A magnetic skyrmionium (also called 2$\pi$-skyrmion) can be understood as a skyrmion - a topologically non-trivial magnetic whirl - which is situated in the center of a second skyrmion with reversed magnetization. Here, we propose a new optoelectrical writing and deleting mechanism for skyrmioniums in thin films, as well as a reading mechanism based on the topological Hall voltage. Furthermore, we point out advantages for utilizing skyrmioniums as carriers of information in comparison to skyrmions with respect to the current-driven motion. We simulate all four constituents of an operating skyrmionium-based racetrack storage device: creation, motion, detection and deletion of bits. The existence of a skyrmionium is thereby interpreted as a '1' and its absence as a '0' bit.