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Spin injection into a ballistic semiconductor microstructure

Vladimir Ya. Kravchenko·Emmanuel I. Rashba
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Abstract

A theory of spin injection across a ballistic ferromagnet-semiconductor-ferromagnet junction is developed for the Boltzmann regime. Spin injection coefficient $γ$ is suppressed by the Sharvin resistance of the semiconductor $r_N^*=(h/e^2)(π^2/S_N)$, where $S_N$ is the Fermi-surface cross-section. It competes with the diffusion resistances of the ferromagnets $r_F$, and $γ\sim r_F/r_N^*\ll 1$ in the absence of contact barriers. Efficient spin injection can be ensured by contact barriers. Explicit formulae for the junction resistance and the spin-valve effect are presented.

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Vladimir Ya. Kravchenko, Emmanuel I. Rashba. 2002-11-02. Spin injection into a ballistic semiconductor microstructure. https://doi.org/10.1103/physrevb.67.121310

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