Crystallographically amorphous ferrimagnetic alloys: Comparing a localized atomistic spin model with experiments

Ostler, Thomas A.; Evans, Richard F.L.; Chantrell, Roy W.; Atxitia, Unai; Chubykalo-Fesenko, Oksana; Radu, Ilie; Abrudan, Radu; Radu, Florin; Tsukamoto, Arata; Itoh, A.; Kirilyuk, Andrei; Rasing, Theo; Kimel, Alexey

Abstract

We present a computational model of crystallographically amorphous ferrimagnetic alloys using a stochastic Landau-Lifshitz-Gilbert equation of motion for atomistic spins and an atomistic spin Hamiltonian with Heisenberg exchange. The spontaneous equilibrium magnetization is calculated and a comparison with a mean field model is made. The simulations show excellent agreement with experiments on GdFeCo using x-ray magnetic circular dichroism to determine the individual sublattice magnetizations. The calculated temperature dependence of the magnetization shows a polarization of the Gd sublattice leading to a common Curie temperature, in agreement with the experimental data. The intersublattice exchange is shown to be an important energy transfer channel for ultrafast dynamics. © 2011 American Physical Society.

Citation

Ostler, T. A., Evans, R. F., Chantrell, R. W., Atxitia, U., Chubykalo-Fesenko, O., Radu, I., Abrudan, R., Radu, F., Tsukamoto, A., Itoh, A., Kirilyuk, A., Rasing, T., & Kimel, A. (2011). Crystallographically amorphous ferrimagnetic alloys: Comparing a localized atomistic spin model with experiments. Physical review B: Condensed matter and materials physics, 84(2), https://doi.org/10.1103/PhysRevB.84.024407

• Journal Article Type: Article
• Publication Date: Jul 6, 2011
• Deposit Date: Jun 15, 2022
• Journal: Physical Review B - Condensed Matter and Materials Physics
• Print ISSN: 1098-0121
• Electronic ISSN: 1550-235X
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 84
• Issue: 2
• DOI: https://doi.org/10.1103/PhysRevB.84.024407
• Public URL: https://hull-repository.worktribe.com/output/4014337