Talk (non-conference) (Invited)

FZJ-2022-01899

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Tuning the magnetic and structural properties of Fe3O4 films grown on Nb:SrTiO3 substrates

Xu, Y. (Corresponding author)FZJ*

2022

Please use a persistent id in citations: http://hdl.handle.net/2128/31016

Abstract: Tuning magnetic oxide phases via redox reactions across their heterointerfaces makesthem useful for spintronic and memristive device applications. In Mai Hussein Hamed’sprevious study, an interesting insight of tuning the Fe3O4 thin films on SrTiO3 substratesinterface via annealing was given [1]. Inspired by memristor, I further studied totun it by applying electric field. Using controlled film-substrate interfaces and a smallelectric field, it is possible that an oxidation/reduction reaction occurs which leads toa reversible phase transition in the thin film.The quality of Fe3O4 thin films is sensitive to the growth parameters. In my talk, Iwill first introduce the growth optimization of Fe3O4 thin films on Nb-STO using PLD.The characterization of Fe3O4 thin films structural and magnetic qualities is introducedin detail. Furthermore, using magnetometry, we can detect the Verwey transition whichis a strong indicator of the oxygen content in the Fe3O4 films. I will present the observationof a strong change in the Verwey transition with an applied electric field. Thiscan be explained by oxygen diffusion through the interface which leads to a reversiblephase transition from Fe3O4(magnetite) to γ-Fe2O3(maghemite). Additionally, we investigatethe structural transitions using ex-situ XRD. In the outlook, I will furtherpropose the possible in-situ measurement while applying voltage in order to study theoxygen stoichiometry, as well as the possible tuning by annealing.

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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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