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Stabilization of magnetic helix in exchange-coupled thin films.

ABSTRACT: Based on micromagnetic simulations, we report on a novel magnetic helix in a soft magnetic film that is sandwiched between and exchange-coupled to two hard magnetic layers with different anisotropies. We show that such a confined helix stays stable without the presence of an external magnetic field. The magnetic stability is determined by the energy minimization and is a result of an internal magnetic field created by the exchange interaction. We show that this internal field stores a magnetic energy density of a few kJ/m(3). We also find that it dramatically modifies ferromagnetic resonances, such that the helix can be used as a ferromagnetic resonance filter and a fast acting attenuator.

SUBMITTER: Dzemiantsova LV

PROVIDER: S-EPMC4633621 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Stabilization of magnetic helix in exchange-coupled thin films.

Dzemiantsova L V LV Meier G G Röhlsberger R R

Scientific reports 20151105

Based on micromagnetic simulations, we report on a novel magnetic helix in a soft magnetic film that is sandwiched between and exchange-coupled to two hard magnetic layers with different anisotropies. We show that such a confined helix stays stable without the presence of an external magnetic field. The magnetic stability is determined by the energy minimization and is a result of an internal magnetic field created by the exchange interaction. We show that this internal field stores a magnetic e ...[more]

PMID: 26537574

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