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Correlated electrons in optically-tunable quantum dots: Building an electron dimer molecule

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 نشر من قبل Massimo Rontani
 تاريخ النشر 2010
  مجال البحث فيزياء
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We observe the low-lying excitations of a molecular dimer formed by two electrons in a GaAs semiconductor quantum dot in which the number of confined electrons is tuned by optical illumination. By employing inelastic light scattering we identify the inter-shell excitations in the one-electron regime and the distinct spin and charge modes in the interacting few-body configuration. In the case of two electrons a comparison with configuration-interaction calculations allows us to link the observed excitations with the breathing mode of the molecular dimer and to determine the singlet-triplet energy splitting.



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