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Half-metallicity and efficient spin injection in AlN/GaN:Cr (0001) heterostructure

J. E. Medvedeva·A. J. Freeman·X. Y. Cui·C. Stampfl·N. Newman
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Abstract

First-principles investigations of the structural, electronic and magnetic properties of Cr-doped AlN/GaN (0001) heterostructures reveal that Cr segregates into the GaN region, that these interfaces retain their important half-metallic character and thus yield efficient (100 %) spin polarized injection from a ferromagnetic GaN:Cr electrode through an AlN tunnel barrier - whose height and width can be controlled by adjusting the Al concentration in the graded bandgap engineered Al(1-x)Ga(x)N (0001) layers.

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J. E. Medvedeva, A. J. Freeman, X. Y. Cui, C. Stampfl, N. Newman. 2004-10-18. Half-metallicity and efficient spin injection in AlN/GaN:Cr (0001) heterostructure. https://doi.org/10.1103/physrevlett.94.146602

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