Poster (Invited)

FZJ-2022-04554

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Investigation of the oxygen vacanciy diffusion via applied electric field in oxide heterostructures

Xu, Y.FZJ* ; Hussein, M.FZJ* ; Bednarski-Meinke, C.FZJ* ; Qdemat, A.FZJ* ; Tober, S.FZJ* ; Kentzinger, E.FZJ* ; Petracic, O.FZJ* ; Brückel, T.FZJ*

2022

Please use a persistent id in citations: http://hdl.handle.net/2128/32492

Abstract: The ability to tune magnetic oxide phases via redox reactions across their heterointerfacescould lead to useful spintronic and memristive device applications. By applyinga small electric field, oxidation/reduction occurs at the heterointerface and leads to areversible phase transition [1-2]. In this poster, we present the preparation and characterizationof epitaxial Fe3O4 thin films grown on TiO2 - terminated Nb:STO via pulsedlaser deposition (PLD). Using magnetometry, we detect the Verwey transition; a strongindicator of the oxygen content in the Fe3O4 films. We observe a significant decreasein the Verwey transition temperature with applied positive electric field. This could bebe explained by oxygen diffusion through the interface which then leads to a reversiblephase transition from Fe3O4(magnetite) to γ-Fe2O3(maghemite). The oxygen diffusionalso induces a structural change of the crystal lattice. Using x-ray diffraction (XRD),we can investigate the strain and structural transitions in the out-of-plane direction.Interestingly, by GISAXS we observe a decrease of the magnetite domain size for thesample after applying the electric field. We surmise this arises due to oxygen diffusionbetween interfaces. PNR measurements are being planned to confirm this.

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Contributing Institute(s):

1. Streumethoden (JCNS-2)
2. Streumethoden (PGI-4)
3. JARA-FIT (JARA-FIT)

Research Program(s):

1. 632 - Materials – Quantum, Complex and Functional Materials (POF4-632) (POF4-632)
2. 6G4 - Jülich Centre for Neutron Research (JCNS) (FZJ) (POF4-6G4) (POF4-6G4)

Appears in the scientific report 2022

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Database coverage:

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