Laser-Induced Skyrmion Writing and Erasing in an Ultrafast Cryo-Lorentz Transmission Electron Microscopy

TL;DR

This study demonstrates ultrafast laser-induced writing and erasing of skyrmions in FeGe using cryo-Lorentz TEM, revealing their dynamic behavior and recovery times under optical excitation.

Contribution

It introduces a method to control skyrmions with light pulses and directly observes their evolution at high temporal resolution.

Findings

Skyrmions can be written and erased with light pulses across various temperatures and magnetic fields.

The skyrmion lattice remains structurally stable during laser-induced demagnetization.

Recovery of the skyrmion state occurs within microseconds, depending on cooling rates.

Abstract

We demonstrate that light-induced heat pulses of different duration and energy can write skyrmions in a broad range of temperatures and magnetic field in FeGe. Using a combination of camera-rate and pump-probe cryo-Lorentz Transmission Electron Microscopy, we directly resolve the spatio-temporal evolution of the magnetization ensuing optical excitation. The skyrmion lattice was found to maintain its structural properties during the laser-induced demagnetization, and its recovery to the initial state happened in the sub-{\mu}s to {\mu}s range, depending on the cooling rate of the system.