Experimental determination of domain wall width and spin stiffness constant in ferromagnetic (Ga,Mn)As with perpendicular easy axis
Résumé
The magnetic domain structure and hysteresis cycles of (Ga,Mn)As are investigated using magneto-optical imaging. The anisotropy constants and the magnetization are obtained from ferromagnetic resonance and SQUID magnetometry measurements, respectively. The experimental data are analyzed using domain theory for ferromagnetic films with strong uniaxial anisotropy. We obtain lower and upper boundaries for the micromagnetic parameters: the domain wall specific energy, the domain wall width and the spin stiffness constant. (c) 2007 Elsevier B.V. All rights reserved.