Metallic-type oscillatory interlayer exchange coupling across an epitaxial FeSi spacer

We study interlayer exchange coupling in epitaxial Fe/Fe0.56Si0.44/Fe trilayers. Iron-silicide spacers with high structural and compositional homogeneity for thicknesses up to 34 Angstrom are grown by coevaporation from two electron-beam sources. The coupling strength oscillates with spacer thickness for temperatures from 20 to 300 K with two antiferromagnetic maxima at 12 and 26 Angstrom, and it clearly increases with decreasing temperature down to 80 K. We conclude that the coupling across ordered Fe1-xSix (x approximate to 0.5) is described by the conventional theory of interlayer coupling across metallic spacers