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Magnetic interactions in exchange-coupled yet unbiased IrMn/NiCu bilayers
R Cichelero1, A Harres, K D Sossmeier
1Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, 91501-970 Rio Grande do Sul, Brazil.
Journal of Physics. Condensed Matter : an Institute of Physics Journal
|September 26, 2013
Summary
This study on ferromagnet/antiferromagnet bilayers shows ion irradiation modifies film coercivity. Remanence plot analysis distinguishes interface coupling from internal magnetic interactions.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Magnetism
Background:
- Exchange-coupled ferromagnet/antiferromagnet (FM/AF) bilayers are crucial for spintronic devices.
- Controlling interfacial magnetic properties through post-deposition treatments is essential for device performance.
Purpose of the Study:
- To investigate the effects of ion irradiation (He, Ge) on the magnetic properties of FM/AF bilayers.
- To analyze the nature of magnetic interactions and their correlation with coercivity variations.
- To differentiate between intra-layer and interfacial magnetic interactions.
Main Methods:
- Experimental measurements of magnetization.
- Ion irradiation (He, Ge) at 40 keV with varying fluences.
- Remanence plots technique.
- Numerical simulations using the Landau-Lifshitz-Gilbert equation.
Main Results:
- Coercivity of FM/AF bilayers significantly varies with ion irradiation fluence.
- Remanence plot analysis successfully distinguished intra-layer FM interactions from FM/AF interfacial coupling.
- Demagnetizing interaction effects were observed without the presence of dipolar interactions.
Conclusions:
- Ion irradiation provides a method to selectively modify magnetic properties in FM/AF bilayers.
- The remanence plots technique coupled with simulations offers selective information on post-deposition treatment effects in each layer.
- Understanding these modifications is key for tailoring spintronic device functionalities.
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