Interaction between magnetic nanoparticles in clusters

Andrea Ehrmann; Tomasz Blachowicz; Andrea Ehrmann; Tomasz Blachowicz

doi:10.3934/matersci.2017.2.383

AIMS Materials Science

2017, Volume 4, Issue 2: 383-390. doi: 10.3934/matersci.2017.2.383

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Interaction between magnetic nanoparticles in clusters

Andrea Ehrmann ^{1
,
,},
Tomasz Blachowicz ²

1.
Faculty of Engineering and Mathematics, Bielefeld University of Applied Sciences, 33619 Bielefeld, Germany
2.
Institute of Physics—Center for Science and Education, Silesian University of Technology, 44-100 Gliwice, Poland

Received: 28 December 2016 Accepted: 19 February 2017 Published: 21 February 2017

Micromagnetic simulations are often used to model the magnetic properties of nanoparticles, depending on their shape and dimension as well as other parameters. Due to the significant increase in computing time for large-scale models, simulations are regularly restricted to a single magnetic nanoparticle. Applications in bit-patterned media etc., however, necessitate large clusters of nanostructures. In our recent works, the deviations of magnetic properties and magnetization reversal processes, comparing single nanoparticles and small clusters, were investigated using the micromagnetic simulation OOMMF. The studies concentrated on a special fourfold shape which has been shown before to offer four stable states at remanence, allowing for creating quaternary bit-patterned media with two bits storable in one position. The influence of downscaling was examined by varying the sample dimensions without changing the particle shape. The results show that in case of the special square nanostructures under investigation, the largest nanoparticles experience the strongest effect by being included in a cluster, while the technologically more relevant smaller nanoparticles have similar magnetic properties and identical magnetization reversal processes for single and clustered particles.
- micromagnetic simulation,
- magnetic nanoparticles,
- nanoparticle cluster,
- OOMMF,
- stable intermediate state,
- lithography
Citation: Andrea Ehrmann, Tomasz Blachowicz. Interaction between magnetic nanoparticles in clusters[J]. AIMS Materials Science, 2017, 4(2): 383-390. doi: 10.3934/matersci.2017.2.383

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Abstract

Micromagnetic simulations are often used to model the magnetic properties of nanoparticles, depending on their shape and dimension as well as other parameters. Due to the significant increase in computing time for large-scale models, simulations are regularly restricted to a single magnetic nanoparticle. Applications in bit-patterned media etc., however, necessitate large clusters of nanostructures. In our recent works, the deviations of magnetic properties and magnetization reversal processes, comparing single nanoparticles and small clusters, were investigated using the micromagnetic simulation OOMMF. The studies concentrated on a special fourfold shape which has been shown before to offer four stable states at remanence, allowing for creating quaternary bit-patterned media with two bits storable in one position. The influence of downscaling was examined by varying the sample dimensions without changing the particle shape. The results show that in case of the special square nanostructures under investigation, the largest nanoparticles experience the strongest effect by being included in a cluster, while the technologically more relevant smaller nanoparticles have similar magnetic properties and identical magnetization reversal processes for single and clustered particles.

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