Damping of confined modes in a ferromagnetic thin insulating film: angular momentum transfer across a nanoscale field-defined interface.

We observe a dependence of the damping of a confined mode of precessing ferromagnetic magnetization on the size of the mode. The micron-scale mode is created within an extended, unpatterned yttrium iron garnet film by means of the intense local dipolar field of a micromagnetic tip. We find that the damping of the confined mode scales like the surface-to-volume ratio of the mode, indicating an interfacial damping effect (similar to spin pumping) due to the transfer of angular momentum from the confined mode to the spin sink of ferromagnetic material in the surrounding film.

Control of magnetocrystalline anisotropy by epitaxial strain in double perovskite Sr(2)FeMoO(6) films.

We demonstrate tuning of magnetocrystalline anisotropy in high-quality Sr(2)FeMoO(6) epitaxial films over a range of several thousand Gauss using strain induced by epitaxial growth on substrates of varying lattice constants. Spectroscopic measurements reveal a striking, linear dependence of the out-of-plane anisotropy on the strain-induced tetragonal distortion of the Sr(2)FeMoO(6) lattice. This anisotropy can be tuned from +2000 to -3300 Oe, a range sufficient to rotate the easy axis from in plane to out of plane.