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Spin Dependent Tunneling in FM|semiconductor|FM structures

S. Vutukuri·M. Chshiev·W. H. Butler
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Abstract

Here we show that ordinary band structure codes can be used to understand the mechanisms of coherent spin-injection at interfaces between ferromagnets and semiconductors. This approach allows the screening of different material combinations for properties useful for obtaining high tunneling magnetoresistance (TMR). We used the Vienna Ab-initio Simulation Code (VASP) to calculate the wave function character of each band in periodic epitaxial Fe(100)|GaAs(100) and Fe(100)|ZnSe(100) structures. It is shown that Fe wave functions of different symmetry near Fermi energy decay differently in the GaAs and ZnSe.

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S. Vutukuri, M. Chshiev, W. H. Butler. 2005-09-21. Spin Dependent Tunneling in FM|semiconductor|FM structures. https://doi.org/10.1063/1.2151805

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