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arXiv · 0911.2247

Dynamically broken symmetry in periodically gated quantum dots: Charge accumulation and dc-current

T. Kwapinski·S. Kohler·P. Hanggi
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Abstract

Time-dependent electron transport through a quantum dot and double quantum dot systems in the presence of polychromatic external periodic quantum dot energy-level modulations is studied within the time evolution operator method for a tight-binding Hamiltonian. Analytical relations for the dc-current flowing through the system and the charge accumulated on a quantum dot are obtained for the zero-temperature limit. It is shown that in the presence of periodic perturbations the sideband peaks of the transmission are related to combination frequencies of the applied modulations. For a double quantum dot system under the influence of polychromatic perturbations the quantum pump effect is studied in the absence of source-drain and static bias voltages. In the presence of spatial symmetry the charge is pumped through the system due to broken generalized parity symmetry.

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T. Kwapinski, S. Kohler, P. Hanggi. 2009-11-11. Dynamically broken symmetry in periodically gated quantum dots: Charge accumulation and dc-current. https://arxiv.org/abs/0911.2247

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