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arXiv · cond-mat/0408204

Towards half-metallic interfaces: the Co$_2$CrAl/InP contacts

Abstract

Although the interest on half-metallic Heusler alloys, susceptible to be used in spintronic applications, has considerably grown, their interfaces with semiconductors show very low spin-polarization. I identify mechanisms which can keep the high spin-polarization at the interface (more than 80% of the electrons at the Fermi level are of majority spin) although the half-metallicity is lost. The large enhancement of the Cr moment at the interface between a CrAl terminated Co$_2$CrAl(001) spacer and the InP(001) semiconductor weakens the effect of the interface states resulting in this high spin-polarization. On the other hand the Co$_2$CrAl/InP interfaces made up by a Co layer and either an In or a P one show a severe decrease of the Co spin moment but Cr in the subinterface layer is bulklike and the resulting spin-polarization is similar to the CrAl-based interfaces.

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I. Galanakis. 2004-08-17. Towards half-metallic interfaces: the Co$_2$CrAl/InP contacts. https://doi.org/10.1088/0953-8984%2F16%2F45%2F022

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