Structure and giant magnetoresistance in zinc ferrite

Abstract

The tunneling structure of ZnFe_3−xO₄ ferrite was confirmed by high resolution electron microscopy (HREM), non-Ohmic I–V curve and kinetics for α-Fe₂O₃ isothermal phase transformation. The Zn_0.41 Fe_2.59 O₄/α-Fe₂O₃ two-phase polycrystalline has a huge tunneling magnetorsistance (TMR) mainly caused by the tunneling structure. The Zn_0.41 Fe_2.59 O₄ grains are separated by insulating α-Fe₂O₃ thin layer boundaries. The pattern of nanostructure was verified by HREM.

Keywords

ferrite / tunneling magnetoresistance / nanostructure / Fe₂O₃

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