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Ferromagnetic proximity effect in F-QDot-S device

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 نشر من قبل Lukas Hofstetter
 تاريخ النشر 2009
  مجال البحث فيزياء
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Ferromagnetic proximity effect is studied in InAs nanowire (NW) based quantum dots (QD) strongly coupled to a ferromagnetic (F) and a superconducting (S) lead. The influence of the F lead is detected through the splitting of the spin-1/2 Kondo resonance. We show that the F lead induces a local exchange field on the QD, which has varying amplitude and a sign depending on the charge states. The interplay of the F and S correlations generates an exchange field related supgap feature. This novel mini-gap allows now the visualization of the exchange field also in even charge states



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