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Quantum dephasing in a gated GaAs triple quantum dot due to nonergodic noise

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 نشر من قبل Matthieu Delbecq
 تاريخ النشر 2015
  مجال البحث فيزياء
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We extract the phase coherence of a qubit defined by singlet and triplet electronic states in a gated GaAs triple quantum dot, measuring on timescales much shorter than the decorrelation time of the environmental noise. In this non-ergodic regime, we observe that the coherence is boosted and several dephasing times emerge, depending on how the phase stability is extracted. We elucidate their mutual relations, and demonstrate that they reflect the noise short-time dynamics.

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