Strength Of Magnetic Anisotropy Research Articles

Magnetic anisotropy strength and surface alloy formation in Mn/Co/Cu(001) overlayers

Magnetic anisotropy strength and surface alloy formation in Mn/Co/Cu(001) overlayers

Theory of interplay of nuclear magnetism and superconductivity inAuIn2

The recently reported [S. Rehmann, T. Herrmannsd\"orfer, and F. Pobel, Phys. Rev. Lett. 78, 1122 (1997)] coexistence of a nuclear magnetic order, with the critical temperature ${T}_{M}=35$ \ensuremath{\mu}K, and superconductivity, with the critical temperature ${T}_{S}=207$ mK, in ${\mathrm{AuIn}}_{2}$ is studied theoretically. It is shown that superconducting $(S)$ electrons and localized nuclear magnetic moments interact predominantly via the contact hyperfine interaction, giving rise to a spiral or domainlike magnetic order in the superconducting phase depending on the strength of magnetic anisotropy. In clean samples $(l>{\ensuremath{\xi}}_{0})$ of ${\mathrm{AuIn}}_{2}$ the oscillatory magnetic order should produce a line of nodes in the quasiparticle spectrum of $S$ electrons. The critical field ${H}_{c}(T=0)$ in the coexistence phase is reduced by a factor of 2 with respect to its bare value.

Domains and magnetization reversal dynamics in Au/Co/Au (1 1 1) ultrathin films: Co and Au thickness dependence

The magnetic anisotropy of epitaxial ultrathin Co-films on Au(1 1 1) depends drastically on Co- or Au-overlayer thickness. We have used polar magneto-optical Kerr effect on stepped-wedge samples to perform ex situ domain imaging, together with in situ and ex situ magnetic aftereffect measurements. Domains configurations and magnetization reversal dynamics were thus investigated versus perpendicular magnetic anisotropy strength. Large changes with Co thickness in Au/Co/Au(1 1 1) sandwiches are observed; they can be interpreted using existing theories. The drastic evolution of the dynamics of the magnetization reversal process with submonolayer Au coverage is attributed to a structural reorganization of the Co-layer with Au deposition, due to surfactant effect.

Various contributions to magnetostriction in amorphous and polycrystalline ferromagnets

Magnetostriction of amorphous ferromagnets with random local anisotropy and of polycrystalline ferromagnets originates both from a modification of the local magnetic anisotropy strength and from a strain-induced reorientation of the easy axes directions of the local structural units. The magnitudes of these two contributions to the magnetoelastic coupling energy and to the effective magnetostriction constant are calculated for materials with hexagonal local magnetic anisotropy.