Title :
Precise Investigation of Domain Pinning Energy in GaMnAs Using Planar Hall Effect and Magnetoresistance Measurements
Author :
Shin, D.Y. ; Chung, S.J. ; Lee, S. ; Liu, X. ; Furdyna, J.K.
Author_Institution :
Dept. of Phys., Korea Univ., Seoul
fDate :
6/1/2007 12:00:00 AM
Abstract :
The planar Hall effect (PHE) and magnetoresistance (MR) measurements have been carried out on a GaMnAs ferromagnetic semiconductor. The PHE and MR spectra exhibit interesting two-step magnetization switching behavior arising from the magnetic anisotropy properties of the system. By fitting the angle-dependent planar Hall resistance (PHR) data taken at 5 kG with the Stoner-Wohlfarth model, the cubic and uniaxial anisotropy constants were independently obtained. The anisotropy constants lead to the precise determination of easy axis direction, which turns out to be in good agreement with the easy axis determined from the angular plot of the switching field. The domain pinning energies were further obtained by fitting the angle dependence of the switching field, including the effect of uniaxial anisotropy
Keywords :
Hall effect; III-V semiconductors; ferromagnetic materials; gallium arsenide; magnetic anisotropy; magnetic domains; magnetic switching; magnetoresistance; manganese compounds; semimagnetic semiconductors; GaMnAs; Hall resistance; MR spectra; Stoner-Wohlfarth model; domain pinning energy; ferromagnetic semiconductor; magnetic anisotropy; magnetization switching; magnetoresistance; planar Hall effect; Anisotropic magnetoresistance; Electrical resistance measurement; Energy measurement; Hall effect; Magnetic anisotropy; Magnetic domain walls; Magnetic materials; Magnetic properties; Magnetization; Physics; (Ga,Mn)As; magnetic anisotropy; magnetic semiconductor; magnetoresistance; pinning energy; planar Hall effect;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2007.894014