Magnetic properties of L21-structured Co2(Cr,Fe)Al films grown on GaAs(001) substrates

Both polycrystalline Co2CrAl and epitaxial Co2FeAl full Heusler alloy thin films with the perfectly ordered L21 structure have been grown onto GaAs(001) substrates at 673 K. The Co2FeAl films, in particular, consist of an almost single phase with the crystalline relationship ofCo2FeAl(001)⟨110⟩‖GaAs(001)⟨110⟩. The element specific magnetic moment per Co atom is found to agree well with the theoretical calculation, while that per Fe atom is decreased. By substituting the Fe with Cr atoms, Co2(Cr,Fe)Al films can preserve these ideal properties and can show half metallicity at room temperature.

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