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Vacuum fluctuations and the spin current in mesoscopic structures with collinear magnetic order

Vitalii K. Dugaev·Patrick Bruno
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Abstract

We show that in magnetic nanostructures with a homogeneous magnetic order, the equilibrium spin current can be nonzero. For example, this is the case of a wide magnetic ring with the magnetization along the ring axis. The physical reason of this effect is a variation of the orientation of anisotropy axis inducing a spin torque acting on the magnetic ions. The mechanism of the spin current generation is related to the quantum vacuum fluctuations in the magnetic system.

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Vitalii K. Dugaev, Patrick Bruno. 2007-05-02. Vacuum fluctuations and the spin current in mesoscopic structures with collinear magnetic order. https://doi.org/10.1103/physrevb.75.201301

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