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Updated: May 15, 2025
09:41
Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides
Published on: May 29, 2018
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Engineering the Magnetic Transition Temperatures and the Rare Earth Exchange Interaction in Oxide Heterostructures
Jonathan Spring1, Natalya Fedorova2, Alexandru B Georgescu3
1Physik-Institut, University of Zurich, 8057 Zurich, Switzerland.
ACS Nano
|April 8, 2025
Summary
Superlattice engineering in oxide heterostructures allows precise control over magnetic properties. Reducing periodicity causes distinct magnetic transitions to merge into a single transition, creating a unique material with enhanced interfacial exchange interactions.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Functional oxide heterostructures' properties are dictated by interface physics.
- Atomically precise deposition techniques enable engineering of these interfaces.
- This control over electronic, magnetic, and structural characteristics allows tuning of emergent properties.
Purpose of the Study:
- Investigate magnetic properties of superlattices made from RE2NiMnO6 (RE = La, Nd) double perovskites.
- Engineer magnetic phase diagrams by adjusting superlattice periodicity at the unit cell level.
- Understand the impact of interfacial effects on magnetic behavior.
Main Methods:
- Fabrication of tailor-made superlattices with varying periodicity.
- Analysis of magnetic properties, including Curie temperatures.
- Application of Landau theory for modeling magnetic transitions.
- Synchrotron X-ray magnetic circular dichroism (XMCD) measurements.
- First-principles calculations.
Main Results:
- Large periodicity superlattices retain individual magnetic transitions of parent compounds.
- Reduced periodicity leads to convergence and merging of Curie temperatures into a single transition.
- Low-periodicity superlattices exhibit unique material behavior due to magnetic order propagation.
- Superlattice interfaces enhance Nd-Ni-Mn exchange interaction.
- Field-induced reversal of Nd magnetic moments observed.
Conclusions:
- Superlattice engineering offers fine-tuning of magnetic properties in oxide heterostructures.
- Interfacial effects significantly influence magnetic behavior and can lead to emergent properties.
- Understanding these interfacial effects is crucial for designing advanced functional materials.
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