Related Experiment Video
Updated: Jul 15, 2026
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Anomalous Crystallinity and Magnetism in Chemically Disordered Coherent Heterostructures
Saeed S I Almishal1, Sai Venkata Gayathri Ayyagari1, Aaron Pearre2
1Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania, USA.
Advanced Materials (Deerfield Beach, Fla.)
|July 14, 2026
Summary
High-entropy oxide (HEO) thin films exhibit anomalous crystallinity. Researchers achieved predictive control over HEO lattice parameters and valence states, creating novel magnetic heterostructures for spintronics.
Area of Science:
- Materials Science
- Solid State Physics
- Thin Film Technology
Background:
- High-entropy oxides (HEOs) uniquely combine chemical disorder with crystalline quality.
- Anomalous crystallinity in HEOs arises from coupled structural, chemical, and valence degrees of freedom.
- Entropy-stabilized conditions are key to HEO properties.
Purpose of the Study:
- To demonstrate predictive control over HEO anomalous crystallinity.
- To engineer HEO heterostructures with programmed lattice parameters and valence states.
- To explore new magnetic macrostates for spintronic applications.
Main Methods:
- Utilizing aliovalent cation substitutions and epitaxial constraints.
- Controlling substrate temperatures and adatom kinetic energy during film growth.
- Fabricating pseudomorphic (ScMgCoNiCuZn)O/(CrMgCoNiCuZn)O (JSc/JCr) heterostructures.
Main Results:
- Achieved precise control of out-of-plane lattice parameters in coherent rock salt HEOs.
- Created pseudomorphic valence interfaces with a 5.5% lattice parameter difference.
- Observed a Co valence switch and a 2x exchange bias boost in JSc/JCr heterostructures.
Conclusions:
- Pseudomorphic valence interfaces with anomalous crystallinity enable new magnetic macrostates.
- These engineered interfaces host emergent magnetic and spintronic functionality.
- Predictive control over HEOs opens pathways for advanced material design.
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