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Influence of quantum confinement on the ferromagnetism of (Ga,Mn)As diluted magnetic semiconductor

Sameer Sapra·D. D. Sarma·S. Sanvito·N. A. Hill
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Abstract

We investigate the effect of quantum confinement on the ferromagnetism of diluted magnetic semiconductor Ga$_{1-x}$Mn$_x$As using a combination of tight-binding and density functional methods. We observe strong majority-spin Mn $d$-As $p$ hybridization, as well as half metallic behavior, down to sizes as small as 20 Åin diameter. Below this critical size, the doped holes are self-trapped by the Mn-sites, signalling both valence and electronic transitions. Our results imply that magnetically doped III-V nanoparticles will provide a medium for manipulating the electronic structure of dilute magnetic semiconductors while conserving the ferromagnetic properties and even enhancing it in certain size regime.

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Sameer Sapra, D. D. Sarma, S. Sanvito, N. A. Hill. 2001-11-24. Influence of quantum confinement on the ferromagnetism of (Ga,Mn)As diluted magnetic semiconductor. https://doi.org/10.1021/nl025516q

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