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Lorentz Transmission Electron Microscopy Image Simulations of Experimental Nano-Chessboard Observations in Co-Pt Alloys

Published online by Cambridge University Press:  01 June 2018

Isha Kashyap ,
Yongmei M. Jin ,
Eric P. Vetter ,
Jerrold A. Floro  and
Marc De Graef
Isha Kashyap
Affiliation:
Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA
Yongmei M. Jin
Affiliation:
Department of Materials Science and Engineering, Michigan Technological University, Houghton, MI 49931, USA
Eric P. Vetter
Affiliation:
Department of Materials Science and Engineering, University of Virginia, Charlottesville, VA 22903, USA
Jerrold A. Floro
Affiliation:
Department of Materials Science and Engineering, University of Virginia, Charlottesville, VA 22903, USA
Marc De Graef*
Affiliation:
Department of Materials Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA
*
Author for correspondence: Marc De Graef, E-mail: degraef@cmu.edu
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Abstract

The magnetization configuration of a novel nano-chessboard structure consisting of L10 and L12 phases in a Co40Pt60 alloy is investigated using Lorentz transmission electron microscopy (LTEM) and micro-magnetic simulations. We show high-resolution LTEM images of nano-size magnetic features acquired through spherical aberration correction in Lorentz Fresnel mode. Phase reconstructions and LTEM image simulations are carried out to fully understand the magnetic microstructure. The experimental Fresnel images of the nano-chessboard structure show zig-zag shaped magnetic domain walls at the inter-phase boundaries between L10 and L12 phases. A circular magnetization distribution with vortex and anti-vortex type arrangement is evident in the phase reconstructed magnetic induction maps as well as simulated maps. The magnetic contrast in experimental LTEM images is interpreted with the help of magnetic induction maps simulated for various relative electron beam-sample orientations inside the TEM.

Keywords

Lorentz transmission electron microscopyphase reconstructionmagnetic phase shiftnano-chessboard structuremagnetic domain wall
Type
Materials Science Applications
Information
Microscopy and Microanalysis , Volume 24 , Issue 3 , June 2018 , pp. 221 - 226
Copyright
© Microscopy Society of America 2018 

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Footnotes

Cite this article: Kashyap I, Jin YM, Vetter EP, Floro JA and De Graef M (2018) Lorentz Transmission Electron Microscopy (TEM) Image Simulations of Experimental Nano-Chessboard Observations in Co-Pt Alloys. Microsc Microanal. doi: 10.1017/S143192761800034X

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