Visualisation of high temperature magnetisation states in magnetite grains using off-axis electron holography

Electron Microscopy and Analysis Group Conference 2015

Almeida, T.P.^1 ; Muxworthy, A.R.^1 ; Kovács, A.^2 ; Williams, W.^3 ; Dunin-Borkowski, R.E.^2

Department of Earth Science and Engineering, South Kensington Campus, Imperial College London, London

SW7 2AZ, United Kingdom^1

Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C), Peter Grünberg Institute, Forschungszentrum Jülich, Jülich

D-52425, Germany^2

School of GeoSciences, University of Edinburgh, Edinburgh

EH9 3JW, United Kingdom^3

关键词: Ceramic methods;    High temperature;    In-situ heating;    Non-uniform;    Off-axis electron holography;    Synthetic basalts;    Thermomagnetic measurement;    Vortex state;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/644/1/012027/pdf
DOI  :  10.1088/1742-6596/644/1/012027

来源: IOP

【 摘 要 】

The production of a synthetic basalt comprising Fe3O4grains (∼ 50 nm to ∼ 500 nm), via a glass ceramic method, has been confirmed using transmission electron microscopy and X-ray diffractometry. Off-axis electron holography combined with in situ heating allowed for the visualisation of non-uniform vortex states present in saturation remanent structures, and their variation approaching the Curie temperature; determined separately by bulk thermomagnetic measurements.