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A possible route to grow a (Mn:Si(1-x)Gex)-based diluted magnetic semiconductor

Antonio J. R. da Silva·A. Fazzio·A. Antonelli
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Abstract

We systematically investigate, using ab initio density-functional theory calculations, the properties of interstitial and substitutional Mn in both Si and Ge, as well as in the Si(1-x)Gex alloy. We show that volume effects are not the main reason Mn prefers to be a subsitutional impurity in pure Ge, and chemical effects, therefore, play an important role. Using realistic models of Si(1-x)Gex, we show that for x approximately greater than 0.16 substitutional Mn in Ge-rich neighborhoods become more stable than interstitial Mn, which may allow the growth of Si-based diluted magnetic semiconductors.

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Antonio J. R. da Silva, A. Fazzio, A. Antonelli. 2003-10-31. A possible route to grow a (Mn:Si(1-x)Gex)-based diluted magnetic semiconductor. https://arxiv.org/abs/cond-mat/0310770

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