Epitaxial Fe3Si films stabilized on GaAs(1Â 1Â 3)A substrates

We report epitaxial growth of the Heusler alloy Fe3Si on high-index GaAs(1 1 3)A substrates by molecular-beam epitaxy. The growth temperature and growth rate are optimized to 250∘C and 0.13 nm/min, respectively, for producing Fe3Si films with structural properties comparable to that of Fe3Si films on GaAs(0 0 1). The layers grown under these conditions exhibit high crystal quality with smoother interface/surface and maintain the [1 1 3] orientation of the GaAs substrate. The Fe-Si alloy composition is varied around the Fe3Si stoichiometry using these optimized growth conditions. The magnetic properties of a typical Fe3Si layer with the best structural properties exhibit a four-fold magnetic anisotropy, as expected from the magnetocrystalline anisotropy.