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Induced ferromagnetism in helium bombarded graphite
Tatiana L Makarova1, Andrei L Shelankov, Svetlana B Lyubchik
1Department of Physics, Umeå University, 90187 Umeå, Sweden.
Journal of Nanoscience and Nanotechnology
|August 22, 2012
Summary
Helium ion irradiation effectively induces ferromagnetism in graphite by creating intrinsic carbon defects. These defects, acting as local magnetic moments, are concentrated near the sample surface and maximum damage points.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Graphite is typically non-magnetic.
- Inducing magnetism in otherwise non-magnetic materials is of significant scientific interest.
- Understanding defect-induced magnetism is crucial for novel electronic applications.
Purpose of the Study:
- To investigate the mechanism of ferromagnetism induction in graphite using helium ion irradiation.
- To identify the locations and nature of magnetic moment formation.
- To correlate magnetic properties with induced defects.
Main Methods:
- Irradiation of graphite samples with helium ions.
- Characterization of induced defects and magnetic properties.
- Analysis of defect distribution and magnetic moment interactions.
Main Results:
- Helium ion irradiation successfully triggered ferromagnetism in graphite.
- The inert nature of helium ions indicates that carbon defects are solely responsible for magnetism.
- Interacting magnetic moments were localized near the sample surface and at the point of maximum defect generation.
Conclusions:
- Helium ion irradiation is a viable method for creating ferromagnetic graphite.
- Intrinsic carbon defects are the origin of local magnetic moments.
- The spatial distribution of defects dictates the magnetic interactions within the material.
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