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Spin injection from the Heusler alloy Co_2MnGe into Al_0.1Ga_0.9As/GaAs heterostructures

X. Y. Dong·C. Adelmann·J. Q. Xie·C. J. Palmstrom·X. Lou·J. Strand·P. A. Crowell·J. -P. Barnes·A. K. Petford-Long
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Abstract

Electrical spin injection from the Heusler alloy Co_2MnGe into a p-i-n Al_0.1Ga_0.9As/GaAs light emitting diode is demonstrated. A maximum steady-state spin polarization of approximately 13% at 2 K is measured in two types of heterostructures. The injected spin polarization at 2 K is calculated to be 27% based on a calibration of the spin detector using Hanle effect measurements. Although the dependence on electrical bias conditions is qualitatively similar to Fe-based spin injection devices of the same design, the spin polarization injected from Co_2MnGe decays more rapidly with increasing temperature.

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X. Y. Dong, C. Adelmann, J. Q. Xie, C. J. Palmstrom, X. Lou, J. Strand, P. A. Crowell, J. -P. Barnes, A. K. Petford-Long. 2004-10-28. Spin injection from the Heusler alloy Co_2MnGe into Al_0.1Ga_0.9As/GaAs heterostructures. https://doi.org/10.1063/1.1881789

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