Ballistic spin injection from Fe„001... into ZnSe and GaAs
نویسندگان
چکیده
We consider the spin injection from Fe into ZnSe and GaAs in the ballistic limit. By means of the ab initio screened Korringa-Kohn-Rostoker method we calculate the ground-state properties of epitaxial FeuZnSe(001) and FeuGaAs(001) heterostructures. Three injection processes are considered: injection of hot electrons and injection of ‘‘thermal’’ electrons with and without an interface barrier. The calculation of the conductance by the Landauer formula shows that these interfaces act like a nearly ideal spin filter, with spin polarization as high as 99%. This can be traced back to the symmetry of the band structure of Fe for normal incidence.
منابع مشابه
Ballistic spin injection and detection in FeÕsemiconductorÕFe junctions
We present ab initio calculations of the spin-dependent electronic transport in Fe/GaAs/Fe and Fe/ZnSe/Fe ~001! junctions simulating the situation of a spin-injection experiment. We follow a ballistic Landauer-Büttiker approach for the calculation of the spin-dependent dc conductance in the linear-response regime, in the limit of zero temperature. We show that the bulk band structure of the lea...
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