Laser-Induced Magnetic Nanostructures with Tunable Topological Properties

TL;DR

This paper demonstrates the creation of nanoscale magnetic topological structures, including Skyrmions, in ferrimagnetic films using ultrashort laser pulses, with tunable properties and stability explained by an analytical model.

Contribution

It introduces a method to generate and observe topologically distinct magnetic structures with tunable properties using laser pulses, without external magnetic fields.

Findings

Magnetic structures as small as 150 nm were created.

Skyrmions were stabilized without external magnetic fields.

Magnetic features with tunable topological characteristics were demonstrated.

Abstract

We report the creation and real-space observation of magnetic structures with well-defined topological properties and a lateral size as low as about 150 nm. They are generated in a thin ferrimagnetic film by ultrashort single optical laser pulses. Thanks to their topological properties, such structures can be classified as Skyrmions of a particular type that does not require an externally applied magnetic field for stabilization. Besides Skyrmions, we are able to generate magnetic features with topological characteristics that can be tuned by changing the laser fluence. The stability of such features is accounted for by an analytical model based on the interplay between the exchange and the magnetic dipole-dipole interactions