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Phonon induced Rabi frequency renormalization of optically driven single InGaAs/GaAs quantum dots

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 نشر من قبل Andrew Ramsay
 تاريخ النشر 2010
  مجال البحث فيزياء
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We study optically driven Rabi rotations of a quantum dot exciton transition between 5 and 50 K, and for pulse-areas of up to $14pi$. In a high driving field regime, the decay of the Rabi rotations is nonmonotonic, and the period decreases with pulse-area and increases with temperature. By comparing the experiments to a weak-coupling model of the exciton-phonon interaction, we demonstrate that the observed renormalization of the Rabi frequency is induced by fluctuations in the bath of longitudinal acoustic phonons, an effect that is a phonon analogy of the Lamb-shift.



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