Total Scattering Cross Section and Spin Motion of Low Energy Electrons Passing through a Ferromagnet

It is shown that the spin asymmetry of the elastic transmission of electrons through ferromagnetic films can approach unity. The polycrystalline Co films are a few nanometers thick and saturated with the magnetization $\overrightarrow{M}$ in the plane. The contribution of spin-productive scattering events is below $5\%$. If the electron spin at incidence is chosen to be perpendicular to $\overrightarrow{M}$, it rotates into the direction of $\overrightarrow{M}$ and also precesses around it.