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arXiv · 1105.1093

Spin-injection spectra of CoFe/GaAs contacts: dependence on Fe concentration, interface and annealing conditions

G. Salis·S. F. Alvarado·A. Fuhrer
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Abstract

Spin injection from Co70Fe30 and Fe contacts into bulk GaAs(001) epilayers is studied experimentally. Using nonlocal measurements, the spin polarization of the differential conductance is determined as a function of the bias voltage applied across the injection interface. The spectra reveal an interface-related minority-spin peak at forward bias and a majority-spin peak at reverse bias, and are very similar, but shifted in energy, for Co70Fe30 and for Fe contacts. An increase of the spin-injection efficiency and a shift of the spectrum correlate with the Ga-to-As ratio at the interface between CoFe and GaAs.

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G. Salis, S. F. Alvarado, A. Fuhrer. 2011-05-05. Spin-injection spectra of CoFe/GaAs contacts: dependence on Fe concentration, interface and annealing conditions. https://doi.org/10.1103/physrevb.84.041307

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