Skip to Main content Skip to Navigation
Theses

Propriétés magnétiques statiques et dynamiques de couches minces de GaMnAs à anisotropie perpendiculaire

Abstract : GaMnAs is a diluted ferromagnetic semiconductor. The ferromagnetic order arises from the exchange interaction between carriers and magnetic atoms. The domain structure and domain wall dynamics of thin GaMnAs layers with perpendicular magnetization have been investigated by Kerr microscopy using a magnetic field pulse technique. Postgrowth annealing suppresses the anisotropic expansion of domain by decreasing the magnetic anisotropy fluctuations. Domain theory has been used to determine the spin stiffness and the domain wall parameter. The study of field-driven domain wall dynamics shows that beyond a creep regime, induced by defects, the Walker and precessional flow regimes are reached. The Gilbert's damping constant, that describe energy dissipation effects, is found to be 30 times larger that the one deduced from ferromagnetic resonance. Its value agrees with a model taking into account the non-conservation of the magnetization modulus.
Complete list of metadatas

Cited literature [85 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00379130
Contributor : Alexandre Dourlat <>
Submitted on : Monday, April 27, 2009 - 4:43:16 PM
Last modification on : Friday, May 29, 2020 - 3:59:55 PM
Document(s) archivé(s) le : Monday, October 15, 2012 - 9:25:18 AM

Identifiers

  • HAL Id : tel-00379130, version 1

Citation

Alexandre Dourlat. Propriétés magnétiques statiques et dynamiques de couches minces de GaMnAs à anisotropie perpendiculaire. Matière Condensée [cond-mat]. Université Pierre et Marie Curie - Paris VI, 2008. Français. ⟨tel-00379130⟩

Share

Metrics

Record views

504

Files downloads

1155