Dynamically broken symmetry in periodically gated quantum dots: Charge accumulation and dc-current
| Autor: | Kwapinski, T., Kohler, S., Hanggi, P. |
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| Rok vydání: | 2009 |
| Předmět: | |
| Zdroj: | Ukr. J. Phys. 55 (2010), 85 |
| Druh dokumentu: | Working Paper |
| Popis: | 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. Comment: 10 pages, 7 figures, to appear in UJP (Ukr.J.Phys.) |
| Databáze: | arXiv |
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