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arXiv · 1011.6399

Tunable energy transfer between dipolar-coupled magnetic disks by stimulated vortex gyration

Hyunsung Jung·Ki-Suk Lee·Dae-Eun Jeong·Youn-Seok Choi·Young-Sang Yu·Dong-Soo Han·Andreas Vogel·Lars Bocklage·Guido Meier·Mi-Young Im·Peter Fischer·Sang-Koog Kim
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Abstract

A wide variety of coupled harmonic oscillators exist in nature1. Coupling between different oscillators allows for the possibility of mutual energy transfer between them2-4 and the information-signal propagation5,6. Low-energy input signals and their transport with low-energy dissipation are the key technical factors in the design of information processing devices7. Here, utilizing the concept of coupled oscillators, we experimentally demonstrated a robust new mechanism for energy transfer between spatially separated dipolar-coupled magnetic disks - stimulated vortex gyration. Direct experimental evidence was obtained by time-resolved soft X-ray microscopy. The rate of energy transfer from one disk to the other was deduced from the two normal modes' frequency splitting caused by dipolar interaction. This mechanism provides the advantages of tunable energy transfer rate, low-power input signal, and low-energy dissipation for magnetic elements with negligible damping. Coupled vortex-state disks are promising candidates for information-signal processing devices that operate above room temperature.

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Hyunsung Jung, Ki-Suk Lee, Dae-Eun Jeong, Youn-Seok Choi, Young-Sang Yu, Dong-Soo Han, Andreas Vogel, Lars Bocklage, Guido Meier, Mi-Young Im, Peter Fischer, Sang-Koog Kim. 2010-11-29. Tunable energy transfer between dipolar-coupled magnetic disks by stimulated vortex gyration. https://doi.org/10.1038/srep00059

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