R&D: DFT Calculation of Intrinsic Properties of Magnetically Hard Phase L10 FePt
Calculations allow to understand discrepancies between previous MAE results for different exchange-correlation potentials.
This is a Press Release edited by StorageNewsletter.com on June 9, 2022 at 2:00 pmarXiv has published an article written by Joanna Marciniak Institute of Molecular Physics, Polish Academy of Sciences, and Institute of Materials Engineering, Poznan University of Technology, Poland, Wojciech Marciniak, Institute of Molecular Physics, Polish Academy of Sciences, and Institute of Physics, Poznan University of Technology, Poland, Mirosław Werwiński, Institute of Molecular Physics, Polish Academy of Sciences.
Abstract: “Due to its strong magnetocrystalline anisotropy, FePt L10 phase is considered as a promising magnetic recording media material. Although the magnetic properties of this phase have already been analyzed many times using density functional theory (DFT), we decided to study it again, emphasizing on full potential methods, including spin-polarized relativistic Korringa-Kohn-Rostoker (SPR-KKR) and full-potential local-orbital (FPLO) scheme. In addition to the determination of exact values of the magnetocrystalline anisotropy constants K1 and K2, the magnetic moments (m), the Curie temperature, and the magnetostriction coefficient, we focused on the investigation of the magnetocrystalline anisotropy energy (MAE) dependence on the magnetic moment values using the fully relativistic fixed spin moment (FSM) method with various exchange-correlation potentials. We present nearly identical MAE(m) curves near the equilibrium point, along with different equilibrium values of MAE and magnetic moments. For a magnetic moment reduced by about 10%, we determined a theoretical MAE maximum in the ground state (0 K) equal to about 20.3 MJ m−3 and independent of the choice of the exchange-correlation potential form. These calculations allow us to understand the discrepancies between the previous MAE results for different exchange-correlation potentials.“