Conference Presentation (Invited)

FZJ-2024-05806

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Investigation of the structural and magnetic properties of thein-terface in Fe3O4/TiO2-Nb:STO heterostructures

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

2024

Abstract: The Fe3O4/Nb:STO system has gathered significant attention due to its potential application in spintronicsand memristors. The interface between Fe3O4 and Nb:STO plays a crucial role in determiningthe overall electronic and magnetic properties of the system. We present an investigation of a 30nm Fe3O4 thin film on a TiO2 terminated Nb-doped SrTiO3 (TiO2-Nb:STO) substrate deposited bypulsed laser deposition (PLD), focusing on the buried interface using Polarized Neutron Reflectometry(PNR), X-ray Magnetic Circular Dichroism (XMCD), and X-ray Reflectometry (XRR).Our study utilizes XRR to assess the structural properties, including roughness and density variations,across the interface. PNR is employed to probe the magnetic depth profile. The combinationof these techniques reveals a 1 unit cell (u.c.) γ-Fe2O3 interlayer between the Fe3O4 thin film andthe Nb:STO substrate and a 2 u.c. γ-Fe2O3 surface layer. XMCD provides element-specific magneticinformation throughout the entire system, confirming the total thickness of γ-Fe2O3 to be 3u.c.The results reveal significant modifications in the magnetic and structural properties at the buriedinterface, driven by interactions between the Fe3O4 film and the TiO2-Nb:STO substrate. Specifically,the presence of the γ-Fe2O3 interlayer and surface layer affects the magnetic coupling of thesystem.

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Contributing Institute(s):

1. Streumethoden (JCNS-2)
2. 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 2024

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