Measurement of the thickness-dependent magnetic anisotropy of Co/GaAs(001)

The structure and magnetic anisotropy of epitaxially grown thin Co films on GaAs(001) are studied as a function of thickness by reflection high energy electron diffraction, x-ray diffraction, and rotating-magneto-optical Kerr effect. The cubic anisotropy constant is determined to be K-1=-6.5x10(4) erg/cm(3) for bcc Co, which is in accordance with the anisotropy evolution of bulk FexCo1-x alloy.