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Published on: November 21, 2019
In situ Lorentz microscopy in an alternating magnetic field
Zentaro Akase1, Daisuke Shindo
1Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 katahira Aobaku Sendai 980-8577, Japan. akase@tagen.tohoku.ac.jp
Journal of Electron Microscopy
|January 20, 2010
Summary
A new alternating magnetizing system enables in situ Lorentz microscopy for observing domain wall motion in soft magnetic materials under alternating magnetic fields. This technique is promising for studying domain wall interactions with defects.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Electron Microscopy
Background:
- In situ Lorentz microscopy is crucial for observing magnetic domain structures.
- Understanding domain wall dynamics in soft magnetic materials is essential for technological applications.
- Previous methods lacked the ability to apply controlled alternating magnetic fields during microscopy.
Purpose of the Study:
- To develop and validate an alternating magnetizing system for in situ Lorentz microscopy.
- To enable the study of soft magnetic materials under dynamic alternating magnetic fields.
- To investigate domain wall motion and its interactions with material defects.
Main Methods:
- Development of a novel alternating magnetizing system for electron microscopy.
- Simulation of electron trajectories within the developed system.
- Application of the system to observe domain wall motion in Sendust (Fe(84.9)Al(5.5)Si(9.6)).
Main Results:
- The system allows independent control over alternating magnetic field frequency and amplitude.
- Objective mini lens defocus can be precisely adjusted.
- Successful observation of domain wall motion in Sendust was achieved.
Conclusions:
- The developed alternating magnetizing system is effective for in situ Lorentz microscopy of soft magnetic materials.
- The system provides a promising platform for investigating domain wall dynamics and defect interactions.
- Further research can extend this technique to a wider range of magnetic materials.
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