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Voltage-controlled electron-hole interaction in a single quantum dot

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 نشر من قبل Alexander H\\\"ogele
 تاريخ النشر 2004
  مجال البحث فيزياء
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The ground state of neutral and negatively charged excitons confined to a single self-assembled InGaAs quantum dot is probed in a direct absorption experiment by high resolution laser spectroscopy. We show how the anisotropic electron-hole exchange interaction depends on the exciton charge and demonstrate how the interaction can be switched on and off with a small dc voltage. Furthermore, we report polarization sensitive analysis of the excitonic interband transition in a single quantum dot as a function of charge with and without magnetic field.



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