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Updated: May 24, 2025
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Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides
Published on: May 29, 2018
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Ultrafast entropy production in nonequilibrium magnets
Finja Tietjen1, R Matthias Geilhufe1
1Department of Physics, Chalmers University of Technology, Gothenburg 412 96, Sweden.
PNAS Nexus
|March 6, 2025
Summary
We developed a new ultrafast thermodynamics framework to model heat and entropy in laser-driven magnetic systems. This research advances understanding of nonequilibrium thermodynamics for spintronics and nanotechnology applications.
Area of Science:
- Physics
- Materials Science
- Thermodynamics
Background:
- Laser-driven magnetic systems exhibit complex thermodynamic behaviors.
- Understanding heat generation and entropy production is crucial for ultrafast magnetic phenomena.
Purpose of the Study:
- To present an ultrafast thermodynamics framework for laser-driven ferromagnetic systems.
- To connect laser pulse magnetic field strength to magnetization dynamics and entropy production.
Main Methods:
- Modeling time-dependent entropy production rates.
- Deducing heat dissipation in FeNi and CoFeB thin films.
- Incorporating inertial spin dynamics into theoretical models.
Main Results:
- Theoretical predictions validated against experimental magnetization dynamics data.
- Insights into thermodynamic processes on picosecond timescales.
- Demonstrated impact of inertial spin dynamics on heat generation.
Conclusions:
- The developed framework offers novel insights into controlling heat production in magnetic systems.
- Advances the understanding of nonequilibrium thermodynamics in magnetic materials.
- Has implications for future experimental protocols in spintronics and nanotechnology.
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