The structure and magnetic anisotropy of amorphous Gd-Co films

The structure of amorphous Gd-Co alloy films has been investigated by electron diffraction. The films were prepared by bias sputtering on liquid nitrogen-cooled NaCl substrates. The films were in the 400-800 A thickness range. Magnetic domains were observed by Lorentz microscopy. Hysteresis loops were measured by Faraday magneto-optic effect with the applied field perpendicular to the film surface. Elastically scattered electron intensity and reduced radial distribution functions are significantly different for the perpendicular anisotropic and in-plan anisotropic films. It can also be deduced from these experimental results that the perpendicular anisotropy is associated with a predominance of Gd-Co atom pairs