Exchange interlayer coupling in Fe/SixFe100−x and Co/Si multilayers

Abstract The Fe/SixFe100−x and Co/Si multilayers have been examined. The strongest antiferromagnetic interlayer coupling, J=−1.94 mJ/m2, was found in Fe/SixFe100−x multilayers for x=100. The analysis of the temperature dependences of remanence to saturation magnetization ratios allowed to find the value of semiconductor spacer layer energy gap (Eg≈200 meV) of the examined structures. It suggests that the Fe–Si phase, responsible for antiferromagnetic coupling is an amorphous-like Fe–Si phase. For Co/Si multilayers a very weak exchange coupling and its oscillatory behavior was observed. It was shown that the growth of the Co on Si occurs in an island growth mode. The evolution of magnetic loop shapes can be successfully explained by the interplay between interlayer coupling and anisotropy terms.