Regensburg 2025 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
MA: Fachverband Magnetismus
MA 23: Focus Session: Magneto-Transport and Magneto-Optics of Higher Orders in Magnetization I
MA 23.8: Talk
Wednesday, March 19, 2025, 12:15–12:30, H20
Anisotropy of the contributions to the orbital magnetization — •Milan Vrána1,2 and Jaroslav Hamrle1,2 — 1Charles University, Prague, Czech Republic — 2Czech Technical University, Prague, Czech Republic
The general definition of orbital magnetization is the change in the grand canonical potential, Ω, with respect to the external magnetic field: morb = −∂ Ω / ∂ B. The orbital magnetization consists of two distinct contributions [1]. The first term originates from the orbital motion of electrons and is given by mdip = −e/2 ⟨ ψ | r × v | ψ ⟩. The second term, mkden, has been reinterpreted as arising from changes in the density of k-points in phase space due to the concurrent presence of both the magnetic field and the Berry curvature, Ω [2]. This violates Liouville’s theorem, leading to an expansion or contraction of the phase space volume by a factor of (1 + e/ℏ B · Ω). In the model material bcc Fe, we demonstrate that mkden is negligible in the [100] magnetization direction, whereas mdip is negligible in the [111] direction. It demonstrates different nature of the orbital magnetization for different magnetization directions. However, the magnitude of the total orbital magnetization, morb = mdip + mkden, remains nearly independent of the magnetization direction.
- [1] F. Aryasetiawan, K. Karlsson, Modern theory of orbital magnetic moment in solids, J. Phys. Chem. Solids 128, 87 (2019).
- [2] Di. Xiao, Berry Phase Modification to Electron Density of States and Its Applications, dissertation, Texas University (2007).
Keywords: orbital magnetization; Berry curvature