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Diffusion equation and spin drag in spin-polarized transport

Karsten Flensberg·Thomas Stibius Jensen·Niels Asger Mortensen
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Abstract

We study the role of electron-electron interactions for spin polarized transport using the Boltzmann equation and derive a set of coupled transport equations. For spin polarized transport the electron-electron interactions are important, because they tend to equilibrate the momentum of the two spin species. This ``spin drag'' effect enhances the resistivity of the system. The enhancement is stronger the lower the dimension and should be measurable in for example a two dimensional electron gas with ferromagnetic contacts. We also include spin flip scattering which has two effects: it equilibrates the spin density imbalance and, provided it has a non s-wave component, also the current imbalance.

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Karsten Flensberg, Thomas Stibius Jensen, Niels Asger Mortensen. 2001-07-06. Diffusion equation and spin drag in spin-polarized transport. https://doi.org/10.1103/physrevb.64.245308

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