Positron tunneling and emission from pseudomorphically grown Ni films on Cu substrates

Magnetoelastic Interactions at Surfaces and Interfaces

The contribution of strains to anomalous surface and interface magnetic anisotropies cannot be analyzed quantitatively without knowledge of the ME coupling coefficients there. We have measured the ME coupling coefficients Bs near the surface (~0.5nm) of two amorphous alloys, Fe77Cr6B17 (with bulk magnetostriction λs = +7 × 10−6) and Co76Cr4B20 (λs = -3.8 × 10−6) and found them to differ significantly from the bulk values Bb: Fe-base, Bs = -1.7 × 105 J/m3 (57% of Bb) and Co-base, Bs = 5.8 × 105 J/m3 (three times Bb).

Use of Magneto-Optic Kerr Effect Measurements to Study Strain and Misfit Accommodation in Thin Films of Ni/Cu (100)

We have detected magnetic transitions in Ni/Cu (100) films as a function of Ni thickness through in situ measurements of the magneto-optic Kerr effect (MOKE). Crystalline quality was monitored using in situ RHEED and Auger electron spectroscopy. Films were deposited by molecular beam epitaxy on silicon wafers and cleaved sodium chloride with varying epitaxial Ni layer thicknesses between 10 and 200 A. High-resolution TEM images of these films indicate decreasing misfit dislocation spacing and decreasing strain as measured by moiré fringe analysis with increasing Ni thickness. These observations have been correlated with changes in magnetic anisotropy as measured by MOKE. MOKE, therefore, may provide a tool for in situ monitoring of the kinetics of misfit accommodation in magnetic thin films.