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Coherent manipulation of electronic states in a double quantum dot

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 نشر من قبل Toshimasa Fujisawa
 تاريخ النشر 2003
  مجال البحث فيزياء
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We investigate coherent time-evolution of charge states (pseudo-spin qubit) in a semiconductor double quantum dot. This fully-tunable qubit is manipulated with a high-speed voltage pulse that controls the energy and decoherence of the system. Coherent oscillations of the qubit are observed for several combinations of many-body ground and excited states of the quantum dots. Possible decoherence mechanisms in the present device are also discussed.



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