Oscillatory perpendicular magnetic anisotropy and lattice plane spacing in Fe/Au superlattices

Perpendicular magnetic anisotropy has been investigated for Fe(x ML)/Au(x ML) superlattices (ML: monatomic layer thickness) with x ranging from 1 to 4. The x-ray diffraction analyses indicate the formation of coherent layered structures both for x=integers and nonintegers. However, the perpendicular magnetic anisotropy for x=nonintegers shows different behavior from that for x=integers, and consequently, it oscillates as a function of x with a period of 1 ML. Furthermore, the out-of-plane lattice spacing also oscillates in the same manner.