# Field-free deterministic ultra fast creation of skyrmions by spin orbit torques

## TL;DR

This paper demonstrates a method for deterministic, ultra-fast creation of magnetic skyrmions using spin orbit torque pulses at defects, eliminating the need for external magnetic fields and enabling integration into racetrack devices.

## Contribution

It introduces a novel, field-free technique for controlled skyrmion creation using SOT pulses at defects, advancing skyrmion-based device development.

## Key findings

- Skyrmions can be generated deterministically within subnanoseconds.
- The process does not require external magnetic fields due to DMI effects.
- The method is compatible with integrated racetrack device architectures.

## Abstract

Magnetic skyrmions are currently the most promising option to realize current-driven magnetic shift registers. A variety of concepts to create skyrmions were proposed and demonstrated. However, none of the reported experiments show controlled creation of single skyrmions using integrated designs. Here, we demonstrate that skyrmions can be generated deterministically on subnanosecond timescales in magnetic racetracks at artificial or natural defects using spin orbit torque (SOT) pulses. The mechanism is largely similar to SOT-induced switching of uniformly magnetized elements, but due to the effect of the Dzyaloshinskii-Moriya interaction (DMI), external fields are not required. Our observations provide a simple and reliable means for skyrmion writing that can be readily integrated into racetrack devices.