Magnetic studies of Fe/Cu multilayers

The structural and magnetic properties of sputtered Fe/Cu multilayers are examined as a function of Fe layer thickness tFe by means of X-ray diffraction, Mössbauer spectrometry and superconducting quantum interference magnetometer. The temperature dependence of the spontaneous magnetization M(T) is well described by a T3/2 law in all multilayers in the temperature range 5-300 K. The interface anisotropy constant of Fe/Cu multilayers, Ks, is found to be 0.31 and 0.45 erg/cm2 at 5 and 300 K, respectively. A spin-wave theory has been used to explain the temperature dependence of the magnetization and the approximate values for the bulk exchange interaction Jb, surface exchange interaction Js and the interlayer coupling strength JI for various Fe layer thicknesses have been obtained.