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Highly polarized injection luminescence in forward-biased ferromagnetic-semiconductor junctions at low spin polarization of current

A. M. Bratkovsky·V. V. Osipov
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Abstract

We consider electron tunneling from a nonmagnetic $n$-type semiconductor ($n$-S) into a ferromagnet (FM) through a very thin forward-biased Schottky barrier resulting in efficient extraction of electron spin from a thin $n$-S layer near FM-S interface at low spin polarization of the current. We show that this effect can be used for an efficient polarization radiation source in a heterostructure where the accumulated spin polarized electrons are injected from $n$-S and recombine with holes in a quantum well. The radiation polarization depends on a bias voltage applied to the FM-S junction.

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A. M. Bratkovsky, V. V. Osipov. 2004-07-19. Highly polarized injection luminescence in forward-biased ferromagnetic-semiconductor junctions at low spin polarization of current. https://doi.org/10.1063/1.1867558

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