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Updated: Jul 19, 2025
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Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
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In-plane reorientation induced single laser pulse magnetization reversal
Y Peng1, D Salomoni2, G Malinowski3
1Université de Lorraine, CNRS, IJL, F-54000, Nancy, France.
Nature Communications
|August 17, 2023
Summary
Single Pulse All Optical Switching is now achievable in diverse rare earth-transition metal multilayers, broadening its applicability. This phenomenon
Area of Science:
- Materials Science
- Condensed Matter Physics
- Ultrafast Magnetism
Background:
- Single Pulse All Optical Switching (SP-AOS) was initially demonstrated in GdFeCo ferrimagnets.
- SP-AOS has been recently extended to specific MnRuGa alloys and Tb/Co multilayers.
- These materials required precise thickness and composition for switching.
Purpose of the Study:
- To investigate the generality of SP-AOS in rare earth-transition metal (RE-TM) multilayers.
- To explore the influence of laser pulse duration on switching threshold.
- To understand the underlying magnetization reversal mechanisms.
Main Methods:
- Fabrication of various RE-TM multilayer structures.
- Characterization of magnetic properties.
- Ultrafast optical pump-probe experiments using femtosecond laser pulses.
- Analysis of induced magnetic domain structures.
Main Results:
- SP-AOS demonstrated across a wide range of RE-TM multilayers, indicating increased generality.
- Switching threshold fluence was found to be independent of laser pulse duration.
- Concentric ring domain structures were induced at high laser intensities.
- In-plane magnetization reorientation was observed.
Conclusions:
- SP-AOS is a more general phenomenon in RE-TM multilayers than previously thought.
- The observed features suggest a distinct reversal mechanism compared to Gd-based materials.
- A precessional reversal mechanism successfully explains the experimental observations, including in-plane reorientation and domain structures.
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