Influence of Growth Field on NiFe, Fe$_3$O$_4$, and NiFe/Cr/Fe$_3$O $_4$ Spin-Valves

Thin films of Ni
₈₀
Fe
₂₀
, Fe
₃
O
₄
, as well as Ni
₈₀
Fe
₂₀
/Cr/Fe
₃
O
₄
spin valves, have been grown with and without magnetic fields applied during the deposition, and their magnetotransport properties have been studied at room temperature. The applied field induces an anisotropy in both single layer films, which causes notable differences in their anisotropic magnetoresistance. In the spin valve system, the applied field enables the parallel and antiparallel states to be more well-defined, which reveals a possible giant magnetoresistance in the system. The origin of this signal is likely the interaction of electrons that have been polarized by spin-dependent reflection from the Cr/Fe
₃
O
₄
interface with the Ni
₈₀
Fe
₂₀
interface.