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Electric-field dependent spin diffusion and spin injection into semiconductors

Z. G. Yu·M. E. Flatte
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Abstract

We derive a drift-diffusion equation for spin polarization in semiconductors by consistently taking into account electric-field effects and nondegenerate electron statistics. We identify a high-field diffusive regime which has no analogue in metals. In this regime there are two distinct spin diffusion lengths. Furthermore, spin injection from a ferromagnetic metal into a semiconductor is enhanced by several orders of magnitude and spins can be transported over distances much greater than the low-field spin diffusion length.

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Z. G. Yu, M. E. Flatte. 2002-01-23. Electric-field dependent spin diffusion and spin injection into semiconductors. https://doi.org/10.1103/physrevb.66.201202

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