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Fabrication of Spatially Confined Complex Oxides
Published on: July 1, 2013
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Spatial control of functional properties via octahedral modulations in complex oxide superlattices
1Department of Materials Science and Engineering, Drexel University, 3141 Chestnut Street, 344 LeBow Engineering Building, Philadelphia, Pennsylvania 19104, USA.
Nature Communications
|December 16, 2014
Summary
Engineers can tune oxide interface properties by controlling atomic structure in manganite superlattices. Octahedral superstructures modulate electronic bandwidth and ferromagnetism, impacting Curie temperatures and magnetization.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- Atomic structure control, specifically metal-oxygen octahedra topology, is key for tuning oxide interface properties.
- Isovalent manganite superlattices (SLs) offer a platform for spatial control over electronic bandwidth and ferromagnetism.
Purpose of the Study:
- Investigate isovalent manganite superlattices [(La(0.7)Sr(0.3)MnO(3))n/(Eu(0.7)Sr(0.3)MnO(3))n] × m.
- Explore the creation of octahedral superstructures for spatial control of electronic bandwidth and ferromagnetism.
Main Methods:
- Electron energy loss spectroscopy (EELS) to confirm Mn valence state.
- Scanning transmission electron microscopy (STEM) and X-ray diffraction (XRD) to reveal MnO(6) octahedral rotation modulations.
Main Results:
- EELS confirmed a uniform Mn valence state across the SLs.
- STEM and XRD revealed octahedral rotation modulations synchronized with the SL period.
- Curie temperatures were engineered via octahedral superstructures.
- Modulated magnetization observed in long-period SLs, single transition in short-period SLs.
Conclusions:
- Octahedral superstructures in isovalent manganite SLs enable systematic engineering of functional properties.
- The interplay between SL period and interfacial coupling dictates magnetic behavior, leading to modulated or single magnetic transitions.
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