Skip to Main content Skip to Navigation
Theses

Simulation numérique du comportement hyperfréquence des matériaux ferromagnétiques

Stéphane Labbé 1
1 EDP - Equations aux Dérivées Partielles
LJK - Laboratoire Jean Kuntzmann
Abstract : During the 40's, W.F. Brown introduced the micromagnetism theory to explain the behaviour of non-linear magnetic materials : the ferro and ferrimagnetics.
The model used is based on two main points. The first one is the use of the Landau-Lifchitz partial differential equation, which describes the evolution in time of the magnetisation.The second one is the integration of internal stress as a magnetic excitation.
This excitation is composed of four parts : external, anisotropy, exchange and demagnetisation (magnetostatic). It is this last contribution that induces the greatest difficulties in modelisation.
In this work, the simulation of ferro and ferrimagnetic material behaviour in the microwave domain is studied. Two aspects are focused on : the determination of equilibrium states and the computation of microwave susceptibility.
First of all, the existence of weak solutions in time and space is proved.
A resolution scheme is proposed for the Landau-Lifchitz equations. This scheme is explicit and an adaptative time step is used.
One of the goals is to apply the scheme to very large cubic meshes.
A fast solving method for huge matrices is proposed based upon the use of block-Toeplitz matrices to resolve the magnetostatic problem.
Finally, a preconditonning method is developed improving the resolution of the susceptibility problem (i.e. response computation for an external harmonic excitation).
Finally, numerical results are validate by comparison with a set of experimental results.
Document type :
Theses
Complete list of metadata

Cited literature [44 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00086823
Contributor : Stéphane Labbé <>
Submitted on : Wednesday, July 19, 2006 - 11:26:16 PM
Last modification on : Tuesday, December 8, 2020 - 10:36:14 AM
Long-term archiving on: : Monday, April 5, 2010 - 10:35:01 PM

Identifiers

  • HAL Id : tel-00086823, version 1

Collections

INSMI | CNRS | UGA

Citation

Stéphane Labbé. Simulation numérique du comportement hyperfréquence des matériaux ferromagnétiques. Mathématiques [math]. Université Paris-Nord - Paris XIII, 1998. Français. ⟨tel-00086823⟩

Share

Metrics

Record views

665

Files downloads

1516