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First Principles Calculations of Fe on GaAs (100)

S. Mirbt·B. Sanyal·C. Isheden·B. Johansson
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Abstract

We have calculated from first principles the electronic structure of 0.5 monolayer upto 5 monolayer thick Fe layers on top of a GaAs (100) surface. We find the Fe magnetic moment to be determined by the Fe-As distance. As segregates to the top of the Fe film, whereas Ga most likely is found within the Fe film. Moreover, we find an asymmetric in-plane contraction of our unit-cell along with an expansion perpendicular to the surface. We predict the number of Fe 3d-holes to increase with increasing Fe thickness on $p$-doped GaAs.

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S. Mirbt, B. Sanyal, C. Isheden, B. Johansson. 2003-01-29. First Principles Calculations of Fe on GaAs (100). https://doi.org/10.1103/physrevb.67.155421

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