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Manganese-diffusion-induced n-doping in semiconductor structures containing Ga(Mn)As layers

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 نشر من قبل Tobias Korn
 تاريخ النشر 2008
  مجال البحث فيزياء
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Semiconductor structures using ferromagnetic semiconductors as spin injectors are promising systems for future spintronic devices. Here, we present combined photoluminescence (PL) and time-resolved magneto-optical experiments of a nominally nonmagnetic quantum well(QW) separated by a thin barrier from a ferromagnetic Ga(Mn)As layer. Due to the partial quenching of the PL, we conclude that there is a significant Mn backdiffusion into the QW. Moreover, from the time-resolved measurements, we infer that the Mn leads to n-type doping within the QW, and, in addition, strongly increases the electron spin dephasing time.


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