Athermal All-Optical Femtosecond Magnetization Reversal in GdFeCo

TL;DR

This paper demonstrates that circularly polarized femtosecond laser pulses can reversibly switch magnetization in GdFeCo at ultrafast timescales without heating, showing potential for efficient, heat-free magnetic data storage.

Contribution

It provides experimental evidence of athermal, all-optical femtosecond magnetization reversal in GdFeCo, aligning with recent theoretical predictions and operating at lower temperatures with reduced laser fluence.

Findings

Magnetization reversal occurs at femtosecond timescales.

Reversal is more efficient at lower temperatures.

Switching aligns with theoretical models.

Abstract

Magnetization reversal in GdFeCo by circularly polarized light is shown to occur at the femtosecond time scale. In contrast to the well known laser-assisted magnetization reversal based on the laser heating, we here demonstrate that this femtosecond all-optical magnetization reversal is more efficient at lower temperatures. The lower the temperatures, the smaller the laser fluence required for the switching. This switching is in agreement with a more recent theoretical prediction $[ \text{Phys. Lett. A \textbf{372}, 1915 (2008)} ] $ and demonstrates the feasibility of the femtosecond athermal magnetization reversal.