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arXiv · 1502.05863

$Ab$-$initio$ electronic structure, optical and magneto-optical properties of $MnGaAs$ digital ferromagnetic heterostructures

Patrizia Rosa·Davide Sangalli·Giovanni Onida·Alberto Debernardi
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Abstract

We report on a theoretical study of the electronic, optical and magneto-optical properties of digital ferromagnetic hetero-structures based on $Mn$ $\delta$--doped $GaAs$. We consider different structures corresponding to $Mn$ contents within the range 12-50\% and we study how the system changes as a function of the doping concentration. Our first--principles approach includes the spin-orbit interaction in a fully relativistic pseudopotential scheme and the local fields effect in the description of the optical absorption. We show that $Mn$ $\delta$-doped $GaAs$ shares many properties with the uniformly doped $Ga_{1-x}Mn_xAs$ system, i.e. half-metallicity, similar absorption spectra, and moderate Kerr rotation angles in the visible spectral region.

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Patrizia Rosa, Davide Sangalli, Giovanni Onida, Alberto Debernardi. 2015-02-20. $Ab$-$initio$ electronic structure, optical and magneto-optical properties of $MnGaAs$ digital ferromagnetic heterostructures. https://doi.org/10.1103/physrevb.91.075207

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