A superconducting point contact is used to determine the spin polarization at the Fermi energy of several metals. Because the process of supercurrent conversion at a superconductor-metal interface (Andreev reflection) is limited by the minority spin population near the Fermi surface, the differential conductance of the point contact can reveal the spin polarization of the metal. This technique has been applied to a variety of metals where the spin polarization ranges from 35 to 90 percent: Ni _0.8 Fe _0.2 , Ni, Co, Fe, NiMnSb, La _0.7 Sr _0.3 MnO ₃ , and CrO ₂ .

Exchange hardening of nanostructured two-phase systems composed of an aligned hard phase and a soft phase with high magnetization is investigated using an approach which yields analytic nucleation fields from the micromagnetic vector equation, and accounts for interactions between the soft regions. In suitable structures the nucleation field is proportional to the volume-averaged anisotropy constant. For example, a multilayer composed of alternating 2.4 nm hard-magnetic ${\mathrm{Sm}}_2$ ${\mathrm{Fe}}_{17}$ ${\mathrm{N}}_3$ layers and 9 nm ${\mathrm{Fe}}_{65}$ ${\mathrm{Co}}_{35}$ layers can have an energy product as high as 1 MJ/${\mathrm{m}}^3$ (120 MG Oe), with a rare-earth content of only 5 wt %. Giant energy products may also be achieved in suitable cellular and disordered structures.

Room-temperature ferromagnetism is observed in (110) oriented ZnO films made from targets containing 5 at. % of Sc, Ti, V, Fe, Co, or Ni, but not Cr, Mn, or Cu ions. There are large moments, $2.6{\mu }_B$ and $0.5{\mu }_B/\mathrm{\text{dopant atom}}$ for Co- and Ti-containing oxides, respectively. There is also a moment of $0.3{\mu }_B/\mathrm{S}\mathrm{c}$. Magnetization is very anisotropic, with variations of up to a factor of 3 depending on the orientation of the applied field relative to the substrate. Results are interpreted in terms of a spin-split donor impurity-band model, which can account for ferromagnetism in insulating or conducting high-$k$ oxides with concentrations of magnetic ions that lie far below the percolation threshold. Magnetic moments are associated with two-electron defects in the films as well as unpaired electrons of the $3d$ ions.