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First-principles calculation study on large perpendicular magnetic anisotropy by interfacial modulation in the
Lixiao Bian1, Anhang Zhang2, Hailong Shi3
1College of Electronic and Information Engineering, Shandong University of Science and Technology, Qingdao, 266590, China. lifangfang@sdust.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|June 16, 2026
Summary
Magnetic random-access memory (MRAM) requires large perpendicular magnetic anisotropy (PMA) for AI applications. Fe/NiFe2O4 superlattices show promising PMA, with specific interface configurations yielding high interfacial PMA density.
Area of Science:
- Spintronics
- Materials Science
- Computational Physics
Background:
- Magnetic random-access memory (MRAM) is crucial for next-generation non-volatile spintronics.
- Magnetic tunnel junctions (MTJs) are core components of MRAM.
- Large perpendicular magnetic anisotropy (PMA) is essential for advanced MRAM in AI applications.
Purpose of the Study:
- Investigate the structure and magnetic anisotropy of Fe/NiFe2O4 superlattices.
- Determine the potential of Fe/NiFe2O4 heterostructures for achieving high PMA in MTJs.
Main Methods:
- Utilized first-principles calculations to study Fe/NiFe2O4 superlattices.
- Analyzed atomic structure, magnetic anisotropy, and electronic properties.
Main Results:
- All investigated Fe/NiFe2O4 models demonstrated PMA.
- Identified energetically favorable interface configurations with O atoms on Fe.
- Achieved an interfacial PMA density of up to 0.85 mJ m^-2 for Fe/NiFe2O4 heterostructures with Fe-FeO interfaces.
- Orbital analysis revealed contributions to PMA from Fe d-orbitals, with interfacial Fe showing lower PMA than surface Fe due to specific orbital energy differences.
Conclusions:
- Fe/NiFe2O4 heterostructures exhibit significant PMA.
- The bonding between Fe and O atoms, driven by spin orbital hybridization, enhances PMA.
- These heterostructures are promising candidates for developing high-performance MTJs for MRAM.
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