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Magnetic neutron scattering by magnetic vortices in thin submicron-sized soft ferromagnetic cylinders.

ABSTRACT: Using analytical expressions for the magnetization textures of thin submicron-sized magnetic cylinders in vortex state, we derive closed-form algebraic expressions for the ensuing small-angle neutron scattering (SANS) cross sections. Specifically, for the perpendicular and parallel scattering geometries, we have computed the cross sections for the case of small vortex-center displacements without formation of magnetic charges on the side faces of the cylinder. The results represent a significant qualitative and quantitative step forward in SANS-data analysis on isolated magnetic nanoparticle systems, which are commonly assumed to be homogeneously or stepwise-homogeneously magnetized. We suggest a way to extract the fine details of the magnetic vortex structure during the magnetization process from the SANS measurements in order to help resolving the long-standing question of the magnetic vortex displacement mode.

SUBMITTER: Metlov KL

PROVIDER: S-EPMC4844968 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Magnetic neutron scattering by magnetic vortices in thin submicron-sized soft ferromagnetic cylinders.

Metlov Konstantin L KL Michels Andreas A

Scientific reports 20160426

Using analytical expressions for the magnetization textures of thin submicron-sized magnetic cylinders in vortex state, we derive closed-form algebraic expressions for the ensuing small-angle neutron scattering (SANS) cross sections. Specifically, for the perpendicular and parallel scattering geometries, we have computed the cross sections for the case of small vortex-center displacements without formation of magnetic charges on the side faces of the cylinder. The results represent a significant ...[more]

PMID: 27112640

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