Aberration corrected STEM of iron rhodium nanoislands

Electron Microscopy and Analysis Group Conference 2013

McLaren, M.J.^1 ; Hage, F.S.^2 ; Loving, M.^3 ; Ramasse, Q.M.^2 ; Lewis, L.H.^3 ; Marrows, C.H.^4 ; Brydson, R.M.D.^1

Institute of Materials Research, SPEME, University of Leeds, LS2 9JT, United Kingdom^1

SuperSTEM Laboratory, SciTech Daresbury Campus, Daresbury WA4 4AD, United Kingdom^2

Department of Chemical Engineering, Northeastern University, Boston, MA 02115, United States^3

School of Physics and Astronomy, University of Leeds, LS2 9JT, United Kingdom^4

关键词: Aberration-corrected STEM;    Equiatomic composition;    Ferromagnetic transitions;    Film-substrate interfaces;    High-angle annular dark fields;    Magnetostructural transitions;    Room temperature ferromagnetism;    Scanning transmission electron microscopy;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/522/1/012039/pdf
DOI  :  10.1088/1742-6596/522/1/012039

来源: IOP

【 摘 要 】

Iron-rhodium (FeRh) nanoislands of equiatomic composition have been analysed using scanning transmission electron microscopy (STEM) electron energy loss spec-troscopy(EELS) and high angle annular dark field (HAADF) techniques. Previous magne-tometry results have lead to a hypothesis that at room temperature the core of the islands are antiferromagnetic while the shell has a small ferromagnetic signal. The causes of this effect are most likely to be a difference in composition at the edges or a strain on the island that stretches the lattice and forces the ferromagnetic transition. The results find, at the film-substrate interface, an iron-rich layer ∼ 5 A thick that could play a key role in affecting the magnetostructural transition around the interfacial region and account for the room temperature ferromagnetism.