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Quantum dynamics of tunneling between ferromagnets

Yu-Li Lee·Yu-Wen Lee
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Abstract

We study the Josephson-like spin currents between two ferromagnetic metals by deriving the effective action of the junction. A DC spin Josephson current with the full O(3) symmetry is obtained. By the analogy to the superconducting junctions, we have shown that a time-independent uniform magnetic field can serve as the source of the AC spin Josephson effect. That is, the spin current becomes a periodic function of the time with the period proportional to the inverse of the magnitude of the external magnetic field.

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Yu-Li Lee, Yu-Wen Lee. 2003-11-20. Quantum dynamics of tunneling between ferromagnets. https://doi.org/10.1103/physrevb.68.184413

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