Thermal Fluctuations In The Landau-Lifshitz-Bloch Model
arXiv:2001.02403 · doi:10.1103/PhysRevB.102.024428
Abstract
A formulation for thermal noise in the stochastic form of the Landau Lifshitz Bloch equation used for modeling the magnetization dynamics at elevated temperatures is presented. The diffusion coefficients for thermal fluctuations are obtained via the Fokker-Plank equation using the mean field approximation of the field in defining the free energy. The presented model leads to a mean magnetization consistent with the equilibrium magnetization for small and large particles. The distribution of the magnetization magnitude is of a Poisson-like type rather than the classical Boltzmann distribution. The presented model was tested by studying the equilibrium magnetization in macrospin particles at high temperatures. The model is appealing for multi-scale modeling, such as modeling heat assisted magnetic recording systems and all-optical magnetization reversal
arXiv comment16 pages, 4 figures, 1 appendix
References in corpus (10)
- Atomistic spin model simulations of magnetic nanomaterials
- All-optical control of ferromagnetic thin films and nanostructures
- Fokker-Planck and Landau-Lifshitz-Bloch Equations for Classical Ferromagnets
- Speed limit of FePt spin dynamics on femtosecond timescales
- Thermal fluctuations and longitudinal relaxation of single-domain magnetic particles at elevated temperatures
- Helicity-dependent all-optical domain wall motion in ferromagnetic thin films
- Accumulative magnetic switching of ultra-high-density recording media by circularly polarized light
- Brownian dynamics approach to interacting magnetic moments
- Magnetization dynamics at elevated temperatures
- Dynamics of single-domain magnetic particles at elevated temperatures