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Transport and current noise characteristics of a T-shape double quantum dot system

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 نشر من قبل Ionel Tifrea
 تاريخ النشر 2009
  مجال البحث فيزياء
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We consider the transport and the noise characteristics for the case of a T-shape double quantum dot system using the equation of motion method. Our theoretical results, obtained in an approximation equivalent to the Hartree-Fock approximation, account for non-zero on-site Coulomb interaction in both the detector and side dots. The existence of a non-zero Coulomb interaction implies an additional two resonances in the detectors dot density of states and thereafter affects the electronic transport properties of the system. The systems conductance presents two Fano dips as function of the energy of the localized electronic level in the side dot. The Fano dips in the systems conductance can be observed both for strong (fast detector) and weak coupling (slow detector) between the detector dot and the external electrodes. Due to stronger electronic correlations the noise characteristics in the case of a slow detector are much higher. This setup may be of interest for the practical realization of qubit states in quantum dots systems.



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