Investigation on the magnetism and transport properties of NiMnSb polycrystalline films with oxidized grain surface

Preferentially oriented half-metallic NiMnSb thin films have been fabricated by pulsed-laser deposition on Si(1 0 0) substrates. A nonmagnetic insulating MnOx layer was formed on the NiMnSb grain boundaries due to exposure to the air. In addition to the magnetism, transport properties of the grain-surface-oxided NiMnSb films have been investigated. The insulating conduction and significant magnetoresistance of the NiMnSb films were found to be associated with the insulating manganite oxide layer on the surface of NiMnSb grains.