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arXiv · 0710.5617

Signatures of molecular correlations in the few-electron dynamics of coupled quantum dots

Andrea Bertoni·Juan I. Climente·Massimo Rontani·Guido Goldoni·Ulrich Hohenester
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Abstract

We study the effect of Coulomb interaction on the few-electron dynamics in coupled semiconductor quantum dots by exact diagonalization of the few-body Hamiltonian. The oscillation of carriers is strongly affected by the number of confined electrons and by the strength of the interdot correlations. Single-frequency oscillations are found for either uncorrelated or highly correlated states, while multi-frequency oscillations take place in the intermediate regime. Moreover, Coulomb interaction renders few-particle oscillations sensitive to perturbations in spatial directions other than that of the tunneling, contrary to the single-particle case. The inclusion of acoustic phonon scattering does not modify the carrier dynamics substantially at short times, but can damp oscillation modes selectively at long times.

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Andrea Bertoni, Juan I. Climente, Massimo Rontani, Guido Goldoni, Ulrich Hohenester. 2007-10-30. Signatures of molecular correlations in the few-electron dynamics of coupled quantum dots. https://doi.org/10.1103/physrevb.76.233303

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