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Updated: Aug 13, 2026
11:54
Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures
Published on: February 8, 2018
Ferromagnetism in LaFeO3-LaCrO3 superlattices
1The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567, Japan.
Science (New York, N.Y.)
|May 22, 1998
Summary
Ferromagnetic spin order was achieved in LaCrO3-LaFeO3 superlattices. Artificial layering of Fe3+ and Cr3+ ions enabled ferromagnetic coupling, overcoming previous challenges in Fe-O-Cr materials.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- Ferromagnetic coupling between Fe3+ and Cr3+ ions via oxygen is predicted by established theories (Anderson, Goodenough, Kanamori rules).
- Previous studies on Fe-O-Cr compounds were hindered by random ion distribution, preventing the observation of ferromagnetism.
Purpose of the Study:
- To achieve ferromagnetic spin order in LaCrO3-LaFeO3 superlattices.
- To overcome the limitations of random ion placement in Fe-O-Cr systems.
Main Methods:
- Fabrication of artificial superlattices with precisely layered Fe3+ and Cr3+ ions.
- Growth of superlattices along the [111] crystallographic direction.
Main Results:
- Successful realization of ferromagnetic spin order in the engineered LaCrO3-LaFeO3 superlattices.
- Demonstration that controlled layering overcomes the issue of random ion distribution.
Conclusions:
- Artificial superlattices provide a viable route to achieving predicted ferromagnetic coupling in Fe-O-Cr systems.
- The [111] layered superlattice structure is key to observing ferromagnetism in these materials.
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