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Spin current through a tunnel junction

Matthias Braun·Jürgen König·Jan Martinek
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Abstract

We derive an expression for the spin-current through a tunnel barrier in terms of many-body Green's functions. The spin current has two contributions. One can be associated with angular-momentum transfer by spin-polarized charge currents crossing the junction. If there are magnetic moments on both sides of the tunnel junction, due to spin accumulation or ferromagnetic ordering, then there is a second contribution related to the exchange coupling between the moments.

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Matthias Braun, Jürgen König, Jan Martinek. 2004-11-22. Spin current through a tunnel junction. https://doi.org/10.1016/j.spmi.2004.11.005

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