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Published on: February 5, 2022
Magnetic behaviour of interacting antiferromagnetic nanoparticles
V Markovich1, R Puzniak, Y Skourski
1Department of Physics, Ben-Gurion University of the Negev, 84105 Beer-Sheva, Israel. markoviv@bgu.ac.il
Summary
Interacting La(0.2)Ca(0.8)MnO(3) nanoparticles exhibit complex magnetic properties, with transitions suppressed in smaller particles. Their behavior is explained by a core-shell model involving surface clusters and an antiferromagnetic core.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- La(0.2)Ca(0.8)MnO(3) exhibits a field-induced transition from antiferromagnetic (AFM) to ferromagnetic (FM) states in bulk form.
- Understanding magnetic properties of nanoparticles is crucial for developing advanced magnetic materials.
Purpose of the Study:
- Investigate the magnetic properties of interacting La(0.2)Ca(0.8)MnO(3) nanoparticles.
- Elucidate the influence of particle size and interactions on magnetic transitions.
- Explain the observed magnetic behavior using a core-shell model.
Main Methods:
- Magnetic property measurements on La(0.2)Ca(0.8)MnO(3) nanoparticles.
- Analysis of field-induced magnetic transitions.
- Thermoremanence and isothermoremanence measurements.
- Application of a core-shell model to interpret results.
Main Results:
- Field-induced AFM-to-FM transition observed in bulk La(0.2)Ca(0.8)MnO(3) at high magnetic fields.
- Transition widens and magnetization decreases with increasing particle size.
- Transition is suppressed in small nanoparticles.
- Evidence of irreversible magnetization from nanoparticle shells.
Conclusions:
- The magnetic behavior of La(0.2)Ca(0.8)MnO(3) nanoparticles is attributed to a core-shell structure.
- Surface shells exhibit FM clusters in frustrated coordination with interacting AFM nanoparticles.
- The nanoparticle core behaves as a two-dimensional diluted antiferromagnet.
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