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Updated: Jun 5, 2026
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Optimizing Magnetic Force Microscopy Resolution and Sensitivity to Visualize Nanoscale Magnetic Domains
Published on: July 20, 2022
Giant magnetic moment increase by ultrafast laser light
Sangeeta Sharma1,2, Deepika Gill1, Jyoti Krishna1
1Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Berlin, Germany.
Nature Communications
|June 3, 2026
Summary
Ultrafast laser pulses can now increase magnetic moment in 2D magnets like CrI3. This discovery, using advanced computational methods, reveals a new way light can control magnetic properties at the femtosecond scale.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Optics
Background:
- Femtosecond laser pulses are known to induce ultrafast demagnetization in magnetic materials.
- Controlling magnetic properties with light on ultrafast timescales is a key area of research.
Purpose of the Study:
- To investigate the possibility of inducing an ultrafast increase in magnetic moment using laser pulses.
- To explore the underlying physical mechanisms responsible for laser-induced changes in magnetic moment.
Main Methods:
- Utilized tight-binding calculations.
- Employed state-of-the-art time-dependent density functional theory (TD-DFT).
- Investigated 2D magnets CrI3 and CrSBr.
Main Results:
- Demonstrated an ultrafast, giant increase in magnetic moment, up to 33% (2 μB) in CrI3.
- Identified laser light tuned to the majority spin conduction band as the key factor.
- Revealed that spin-orbit induced valence band spin texture facilitates optical spin-flip transitions.
Conclusions:
- Established a general mechanism for ultrafast light-induced enhancement and reduction of magnetic moment.
- Opened new avenues for controlling magnetic matter with light at femtosecond timescales.
- Highlighted the potential for novel optoelectronic and spintronic applications.
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