Phonon-assisted decoherence and tunneling in quantum dot molecules

A. Grodecka-Grad; J. Förstner

doi:10.1002/pssc.201000824

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arXiv · 1011.2857

Phonon-assisted decoherence and tunneling in quantum dot molecules

A. Grodecka-Grad·J. Förstner

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Abstract

We study the influence of the phonon environment on the electron dynamics in a doped quantum dot molecule. A non-perturbative quantum kinetic theory based on correlation expansion is used in order to describe both diagonal and off-diagonal electron-phonon couplings representing real and virtual processes with relevant acoustic phonons. We show that the relaxation is dominated by phonon-assisted electron tunneling between constituent quantum dots and occurs on a picosecond time scale. The dependence of the time evolution of the quantum dot occupation probabilities on the energy mismatch between the quantum dots is studied in detail.

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A. Grodecka-Grad, J. Förstner. 2010-11-12. Phonon-assisted decoherence and tunneling in quantum dot molecules. https://doi.org/10.1002/pssc.201000824

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