Influence of a Cr seed layer on the magnetic anisotropy of epitaxial Fe/Ag films on MgO(001)

The magnetic anisotropy of epitaxial 300 Å thick Fe films on Ag and Ag/Cr buffer layers on MgO(001) has been studied by ferromagnetic resonance and magneto-optic Kerr effect measurements. The samples were grown by molecular beam epitaxy at ambient temperature. A reduction of the effective magnetization for the samples with a Ag buffer layer is attributed to strain and dislocation formation as seen from X-ray diffraction measurements at low and high angles. In the samples with a Cr seed layer, a higher magnetic anisotropy is found which correlates with a reduced roughness.