Conference Presentation (Invited)

FZJ-2024-05775

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Magnetic Nanocaps: Impact of Curvature on Structural and Magnetic Properties of thin Films

Qdemat, A.FZJ* ; Kentzinger, E.FZJ* ; Buitenhuis, J.FZJ* ; Pütter, S.FZJ* ; Hussein, M.FZJ* ; Bednarski-Meinke, C.FZJ* ; Petracic, O.FZJ* ; Rücker, U.FZJ* ; Brückel, T.FZJ*

2024

Abstract: Magnetic nanocaps, formed by depositing Co/Pd multilayers on highly ordered arrays of silicananospheres, present a promising area of study due to their unique properties. This research focuseson fabricating and characterizing these nanocaps and comparing them to films deposited on flat silicon substrates. Using an advanced drop-casting method, we prepared two-dimensional arraysof silica nanospheres with diameters of 50 nm and 200 nm [1]. The curvature of these nanospheresinduced lateral variations in film thickness, affecting the material properties. Structural analysisusing X-ray reflectivity and Grazing Incidence Small Angle X-ray Scattering (GISAXS) revealed thecurvature-induced morphology. Magnetic measurements via SQUID indicated distinct properties, includinglow coercivity and altered anisotropy axis direction, compared to flat films. Depth-resolvedmagnetization profiles were determined using Polarized Neutron Reflectivity (PNR). Additionally,Grazing Incidence Small Angle Neutron Scattering (GISANS) was employed to investigate in-planelateral magnetic fluctuations. GISANS provided detailed information on the spatial distribution andcorrelations of magnetic domains within the nanocaps, revealing how the curvature and thicknessvariations influence magnetic interactions at the nanoscale. This comprehensive study correlatesthe magnetic and structural properties of thin films with varying thicknesses and nanosphere radii,enhancing our understanding of curvature’s impact on nanostructure formation and magnetic behavior,and guiding the design of functional magnetic materials for technological applications.References:[1] A. Qdemat, et.al., RSC Adv., 10, 2020

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Contributing Institute(s):

1. Streumethoden (JCNS-2)
2. JARA-FIT (JARA-FIT)
3. Biomakromolekulare Systeme und Prozesse (IBI-4)
4. JCNS-4 (JCNS-4)

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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