Ballistic spin injection and detection in FeÕsemiconductorÕFe junctions
نویسندگان
چکیده
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 leads and of the semiconductor, and even more the electronic structure of a clean and abrupt interface, are responsible for a current polarization and a magnetoresistance ratio of almost the ideal 100%, if the transport is ballistic. In particular, we study the significance of the transmission resonances caused by the presence of two interfaces.
منابع مشابه
All optical injection and detection of ballistic charge and spin currents in gallium arsinide, germanium, and silicon
Approved: _________________________ Thesis Supervisor ________________________ Title and Department ________________________ Date ALL OPTICAL INJECTION AND DETECTION OF BALLISTIC CHARGE AND SPIN CURRENTS IN GALLIUM ARSINIDE, GERMANIUM, AND SILICON by Eric Justin Loren A thesis submitted in partial fulfillment of the requirements for the Doctor of Philosophy degree in Physics in the Graduate Col...
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