| About this Abstract |
| Meeting |
2022 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advanced Magnetic Materials for Sensors, Power, and Multifunctional Applications
|
| Presentation Title |
Quantum-confined Charge Transfer that Enhances Magnetic Anisotropy in Lanthanum M-type Hexaferrites |
| Author(s) |
Churna Bhandari, Durga Paudyal |
| On-Site Speaker (Planned) |
Durga Paudyal |
| Abstract Scope |
Iron-based hexaferrites are critical-element-free permanent magnet components of magnetic devices. Of particular interest is electron-doped M-type hexaferrite i.e., LaFe12O19(LaM) in which extra electrons introduced by lanthanum substitution of barium/strontium play a key role in up-lifting the magnetocrystalline anisotropy. We investigate the electronic structure of lanthanum hexaferrite using a localized density functional theory which reproduces semiconducting behavior and identifies the origin of the very large magnetocrystalline anisotropy. Localized charge transfer from lanthanum to the iron at the crystal’s 2a site produces a narrow 3dz2 valence band strongly locking the magnetization along the c-axis. The calculated uniaxial magnetic anisotropy energies from fully self-consistent calculations are nearly double the single-shot values, and agree well with available experiments. The chemical similarity of lanthanum to other rare earths suggests that LaM can host for other rare earths possessing non-trivial 4f electronic states for, e.g., microwave-optical quantum transduction. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Electronic Materials, Magnetic Materials |