摘要： The thermoelectric properties of a quantum dot array (QDA) embedded in a nanowire connected to metallic electrodes are investigated theoretically via the extended Hubbard model in the Coulomb blockade regime. Coupled quantum dots (QDs) with dot number N = 2-5 are considered. It is found that the thermoelectric properties converge to almost the same results when N approaches 5, indicating that our results are applicable for a QDA with a large number of QDs. Our studies indicate that in order to achieve the optimal figure of merit (ZT), it is preferable to have the QD energy levels above the Fermi energy (EF) of the electrodes of the QDA junction. The effects of QD energy level and interdot coupling variations (due to the QD size and position fluctuation) on the thermoelectric properties are also examined. We find that the QD size fluctuation significantly suppresses the maximum ZT in the weak interdot hopping strength (t ,j). We also find that the Seebeck coefficient is insensitive to t ,j and the tunneling rates when the QD energy levels are far above EF. For a given t ,j and large on-site Coulomb interactions, increasing the QD number N in the QDA would suppress the maximum ZT value. It is possible to achieve an optimal ZT larger than 3 by tailoring the physical parameters of the QDA junction system. 其他題名： Nano 其他題名： Nanotechnology 出版者： Bristol: IOP Publishing 出版日期： 2013-05-03 出處： Nanotechnology, 2013-05, Vol.24 (17), p.175403-1-7 資源來源： Institute of Physics Journals 版權： 2013 IOP Publishing Ltd 版權： 2014 INIST-CNRS 識別號： ISSN: 0957-4484 識別號： ISSN: 1361-6528 識別號： EISSN: 1361-6528 識別號： DOI: 10.1088/0957-4484/24/17/175403 識別號： PMID: 23558456 識別號： CODEN: NNOTER
