Revisiting Néel 60 years on: the magnetic anisotropy of $\mathrm{L}{1}_0$ FeNi (tetrataenite)

Abstract

The magnetocrystalline anisotropy energy of atomically ordered $\mathrm{L}{1}_0$ FeNi (the meteoritic mineral tetrataenite) is studied within a first-principles electronic structure framework. Two compositions are examined: equiatomic Fe${}_{0.5}$Ni${}_{0.5}$ and an Fe-rich composition, Fe${}_{0.56}$Ni${}_{0.44}$. It is confirmed that, for the single crystals modelled in this work, the leading-order anisotropy coefficient $K_1$ dominates the higher-order coefficients $K_2$ and $K_3$. To enable comparison with experiment, the effects of both imperfect atomic long-range order and finite temperature are included. While our computational results initially appear to undershoot the measured experimental values for this system, careful scrutiny of the original analysis due to Néel et al. [J. Appl. Phys. 35, 873 (1964)] suggests that our computed value of $K_1$ is, in fact, consistent with experimental values, and that the noted discrepancy has its origins in the nanoscale polycrystalline, multivariant nature of experimental samples, that yields much larger values of $K_2$ and $K_3$ than expected a priori. These results provide fresh insight into the existing discrepancies in the literature regarding the value of tetrataenite's uniaxial magnetocrystalline anisotropy in both natural and synthetic samples.

9 pages, 3 figures, 2 tables

References in corpus (8)

• Electronic structure and magnetic properties of L1_0 binary alloys
• Temperature-dependent magnetocrystalline anisotropy of rare earth/transition metal permanent magnets from first principles: The light RCo${}_5$ (R=Y, La-Gd) intermetallics
• Short-range order and compositional phase stability in refractory high-entropy alloys via first principles theory and atomistic modelling: NbMoTa, NbMoTaW and VNbMoTaW
• Interplay between magnetism and short-range order in medium- and high-entropy alloys: CrCoNi, CrFeCoNi, and CrMnFeCoNi
• Compositional phase stability in medium-entropy and high-entropy Cantor-Wu alloys from an ab initio all-electron, Landau-type theory and atomistic modelling
• Crucial role of Fe in determining the hard magnetic properties of Nd${}_2$Fe${}_{14}$B
• Interplay between chemical order and magnetic properties in L1${}_0$ FeNi (tetrataenite): A First-Principles Study
• Finite-temperature second-order perturbation analysis of magnetocrystalline anisotropy energy of L10-type ordered alloys

Cited by in corpus (5)

• Magnetic anisotropy of L1${}_0$ FeNi (001), (010), and (111) ultrathin films: A first-principles study
• Integrated ab initio modelling of atomic order and magnetic anisotropy for rare-earth-free magnet design: effects of alloying additions in $\mathrm{L}{1}_0$ FeNi
• Magnetization and exchange-stiffness constants of Fe-Al-Si alloys at finite-temperatures: A first-principles study
• Efficient calculation of magnetocrystalline anisotropy energy using symmetry-adapted Wannier functions
• Lattice vacancy migration barriers in Fe-Ni alloys, and why Ni atoms diffuse slowly: An ab initio study