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arXiv · 1206.0615

Tunnelling anisotropic magnetoresistance of Fe/GaAs/Ag(001) junctions from first principles: Effect of hybridized interface resonances

Rudolf Sykora·Ilja Turek
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Abstract

Results of first-principles calculations of the Fe/GaAs/Ag(001) epitaxial tunnel junctions reveal that hybridization of interface resonances formed at both interfaces can enhance the tunnelling anisotropic magnetoresistance (TAMR) of the systems. This mechanism is manifested by a non-monotonic dependence of the TAMR effect on the thickness of the tunnel barrier, with a maximum for intermediate thicknesses. A detailed scan of k-resolved transmissions over the two-dimensional Brillouin zone proves an interplay between a few hybridization-induced hot spots and a contribution to the tunnelling from the vicinity of the Gamma-bar point. This interpretation is supported by calculated properties of a simple tight-binding model of the junction which reproduce qualitatively most of the features of the first-principles theory.

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Rudolf Sykora, Ilja Turek. 2012-06-04. Tunnelling anisotropic magnetoresistance of Fe/GaAs/Ag(001) junctions from first principles: Effect of hybridized interface resonances. https://doi.org/10.1088/0953-8984%2F24%2F36%2F365801

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