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Spin accumulation in ferromagnets

W. N. G. Hitchon·R. W. Chantrell·A. Rebei
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Abstract

Using a density matrix formulation for the effective action, we obtain a set of macroscopic equations that describe spin accumulation in a non-homogeneous ferromagnet. We give a new expression for the spin current which extends previous work by taking into account the symmetry of the ferromagnetic state through a careful treatment of the exchange term between the conduction electrons and the magnetization, i.e, d-electrons. We consider a simple application which has been discussed previously and show that in this case spin accumulation is an interface effect confirming earlier results arrived at by different methods.

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W. N. G. Hitchon, R. W. Chantrell, A. Rebei. 2004-07-02. Spin accumulation in ferromagnets. https://arxiv.org/abs/cond-mat/0407051

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