Excitation transport in quantum devices: analytical time-dependent non-equilibrium green function algorithm
Autor: | Ho, I-Lin |
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Rok vydání: | 2019 |
Předmět: | |
Zdroj: | J. Phys. Condens. Matter 32 (7), 075901 (2019) |
Druh dokumentu: | Working Paper |
DOI: | 10.1088/1361-648X/ab50d3 |
Popis: | This research demonstrates analytical time-dependent non-equilibrium green function (TD-NEGF) algorithms to investigate dynamical functionalities of quantum devices, especially for photon-assisted transports. Together with the lumped element model, we also study the effects of transiently-transferring charges to reflect the non-conservation of charges in open quantum systems, and implement numerical calculations in hetero-junction systems composed of functional quantum devices and electrode-contacts (to the environment). The results show that (i) the current calculation by the analytical algorithms, versus those by conventional numerical integrals, presents superior numerical stability on a large-time scale, (ii) the correction of charge transfer effects can better clarify non-physical transport issues, e.g. the blocking of AC signaling under the assumption of constant device charges, (iii) the current in the long-time limit validly converges to the steady value obtained by standard time-independent density functional calculations, and (iv) the occurrence of the photon-assisted transport is well-identified. Comment: 16 figures, 26 pages. arXiv admin note: substantial text overlap with arXiv:1810.02577 |
Databáze: | arXiv |
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