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Resonant vortex-core reversal in magnetic nano-spheres as robust mechanism of efficient energy absorption and emission.

ABSTRACT: We report on novel vortex-core reversal dynamics in nano-spheres of single-vortex spin configuration as revealed by micromagnetic simulations combined with analytical derivations. When the frequency of an AC magnetic field is tuned to the frequency of the vortex-core precession around the direction of a given static field, oscillatory vortex-core reversals occur, and additionally, the frequency is found to change with both the strength of the applied AC field and the particle size. Such resonant vortex-core reversals in nano-spheres may provide a new and efficient means of energy absorption by, and emission from, magnetic nanoparticles, which system can be effectively implemented in bio-applications such as magnetic hyperthermia.

SUBMITTER: Kim SK

PROVIDER: S-EPMC4987621 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

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Resonant vortex-core reversal in magnetic nano-spheres as robust mechanism of efficient energy absorption and emission.

Kim Sang-Koog SK Yoo Myoung-Woo MW Lee Jehyun J Lee Jae-Hyeok JH Kim Min-Kwan MK

Scientific reports 20160817

We report on novel vortex-core reversal dynamics in nano-spheres of single-vortex spin configuration as revealed by micromagnetic simulations combined with analytical derivations. When the frequency of an AC magnetic field is tuned to the frequency of the vortex-core precession around the direction of a given static field, oscillatory vortex-core reversals occur, and additionally, the frequency is found to change with both the strength of the applied AC field and the particle size. Such resonant ...[more]

PMID: 27531408

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