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Quantum electron splitter based on two quantum dots attached to leads

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 نشر من قبل Francisco Dominguez-Adame
 تاريخ النشر 2006
  مجال البحث فيزياء
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Electronic transport properties of two quantum dots side-coupled to a quantum wire are studied by means of the two impurity Anderson Hamiltonian. The conductance is found to be a superposition of a Fano and a Breit-Wigner resonances as a function of the Fermi energy, when the gate voltages of the quantum dots are slightly different. Under this condition, we analyze the time evolution of a Gaussian-shaped superposition of plane waves incoming from the source lead, and found that the wave packet can be splitted into three packets at the drain lead. This spatial pattern manifests in a direct way the peculiarities of the conductance in energy space. We conclude that the device acts as a quantum electron splitter.



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