A study was made of the magnetic and structural properties of epitaxial bcc Fe(001) films grown at 175C onto molecular beam epitaxially-prepared GaAs(001)-(2 x 4) and -c(4 x 4) reconstructed surfaces, with film thicknesses ranging up to ∼30ML (∼43Å). Measurements were made of the thickness-dependent evolution of the magnetic properties of the Fe films as monitored by in situ magneto-optic Kerr effect. It was found that the magnetic properties and growth mode were similar for both 2 x 4 and c(4 x 4) reconstructions, although the initial adsorption sites and island nucleation as measured by scanning tunnelling microscopy were clearly dominated by the substrate surface reconstruction. The onset of room-temperature ferromagnetism occurred at 6ML for growth on both GaAs surface reconstructions. At this coverage, the measured Curie temperature (∼100C) was significantly reduced from that of bulk α-Fe (770C). The anisotropy was dominated by a uniaxial component such that the two <110> axes were inequivalent for all coverages studied. Shape anisotropy did not appear to play a significant role.

Influence of Substrate Surface Reconstruction on the Growth and Magnetic Properties of Fe on GaAs(001). E.M.Kneedler, B.T.Jonker, P.M.Thibado, R.J.Wagner, B.V.Shanabrook, L.J.Whitman: Physical Review B, 1997, 56, 8163-8