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Updated: Aug 23, 2025
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
8.9K
Proximity-enhanced magnetocaloric effect in ferromagnetic trilayers
M Persson1, M M Kulyk1, A F Kravets1
1Nanostructure Physics, Royal Institute of Technology, 10691 Stockholm, Sweden.
Summary
Atomistic spin dynamics simulations reveal how to enhance the magnetocaloric effect (MCE) in ferromagnetic trilayers. Optimizing the spacer
Area of Science:
- Condensed matter physics
- Materials science
- Spintronics
Background:
- The magnetocaloric effect (MCE) is crucial for magnetic refrigeration technologies.
- Understanding MCE in complex magnetic heterostructures is essential for device optimization.
- Ferromagnetic trilayers offer tunable magnetic properties for MCE applications.
Purpose of the Study:
- To investigate the demagnetization and MCE in strong-weak-strong ferromagnetic trilayers.
- To explore the impact of magnetization reorientation on MCE.
- To identify strategies for enhancing MCE in these systems.
Main Methods:
- Atomistic spin dynamics simulations were employed.
- Simulations focused on reorienting strong ferromagnets from parallel to antiparallel magnetization.
- Entropy was directly calculated from non-trivial spin distributions.
Main Results:
- Non-trivial spin distributions were observed in the antiparallel state.
- The influence of longer-range spin-spin interactions and external switching field strength was analyzed.
- Significant MCE enhancement was achieved by varying local exchange through the spacer.
Conclusions:
- Tailoring the spacer's magnetic dilution can spatially vary local exchange.
- This spatial variation offers a practical method for significantly improving MCE.
- The findings provide a pathway for designing more efficient magnetocaloric materials.
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