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arXiv · 0707.3644

Reversal of spin polarization in Fe/GaAs (001) driven by resonant surface states: First-principles calculations

Athanasios N. Chantis·Kirill D. Belashchenko·Darryl L. Smith·Evgeny Y. Tsymbal·Mark van Schilfgaarde·Robert C. Albers
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Abstract

A minority-spin resonant state at the Fe/GaAs(001) interface is predicted to reverse the spin polarization with voltage bias of electrons transmitted across this interface. Using a Green's function approach within the local spin density approximation we calculate spin-dependent current in a Fe/GaAs/Cu tunnel junction as a function of applied bias voltage. We find a change in sign of the spin polarization of tunneling electrons with bias voltage due to the interface minority-spin resonance. This result explains recent experimental data on spin injection in Fe/GaAs contacts and on tunneling magnetoresistance in Fe/GaAs/Fe magnetic tunnel junctions.

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Athanasios N. Chantis, Kirill D. Belashchenko, Darryl L. Smith, Evgeny Y. Tsymbal, Mark van Schilfgaarde, Robert C. Albers. 2007-07-24. Reversal of spin polarization in Fe/GaAs (001) driven by resonant surface states: First-principles calculations. https://doi.org/10.1103/physrevlett.99.196603

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