Fabrication of FeOx thin films and the modulation of transport and magnetic properties by resistance switching in Au/α-Fe2O3/Pt heterostructure.

It was found that by using the same α-Fe₂O₃ target in fabrication process, an oxygen-deficient and an oxygen-sufficient atmosphere facilitated the formation of Fe₃O₄ and α-Fe₂O₃, respectively. The Au/α-Fe₂O₃/Pt heterostructure showed a memristive bipolar resistance switching. A clear difference was observed in the transport and magnetic properties between the two resistance states. The enhanced conductivity and magnetization in the Au/α-Fe₂O₃/Pt heterostructure are believed to result from an enhanced electron hopping between Fe³⁺-Fe²⁺ pairs and Fe³⁺-O-Fe²⁺ double exchange coupling effect. The enhanced Fe²⁺ comes from a redox transition between two phases (one behaves like Fe₃O₄ and the other like α-Fe₂O₃), due to the electrochemical migration of oxygen vacancies. [ABSTRACT FROM AUTHOR]