Magnetic properties, anisotropy, and microstructure of sputtered rare-earth iron multilayers

A study of compositionally modulated magnetic films of the form Fe/RE, particularly for RE=Nd and Dy, has been performed by vibrating sample magnetometry, ac susceptibility and x-ray diffraction. The relationship between the magnetic properties and the layer thickness was studied systematically for X-Å Fe/Y-Å Dy, as the layer thicknesses X and Y were varied from 1.8 to 20 Å. The ranges of layer thicknesses required for perpendicular anisotropy were determined. The interface and volume anisotropy energies were estimated for X-Å Fe/Y-Å Nd and the differences in the magnetic properties between X-Å Fe/7-Å Dy and X-Å Fe/7-Å Nd are discussed.