本論文利用 tight-binding 模型來研究分析三角型的量子點分子 及 對稱四角型量子點分子之傳輸。借由凱帝旭格林函數(Keldysh-Green`s function )的技巧可以得出系統中的電導值以及西貝克係數。我們將討論量子干涉效應對電導及西貝克係數(Seebeckcoefficient)的影響。此種量子點分子系統有提供兩個傳導路徑允許電子從左電極到右電極，所以具備了產生量子干涉的條件。利用閘極電位來控制量子點的能階進而達到控制量子點的耦合躍遷強度(Hopping strength)，因而可以檢測量子干涉效應。由於我們忽略了量子點間的庫倫作用力，所以結果不適用在量子點有多電子佔據的情況。

The charge of triangular and square quantum dot (QD) molecules (QDMs) is studied by using tight-binding model. The electrical conductance and Seebeck coefficient of QDMs are calculated by Keldysh-Green`s function method. Due to two paths, the quantum interference (QI) effect arising from the coherent tunnelingbetween QDs can be observed. We use the longdistance coherent tunneling mechanism to manipulate QI and examine the effect of QI on the thermoelectric coefficients of QDMs connected to metallic electrodes. Because we have ignored electron Coulomb interactions, our results are limited to the case of QDMs energy levels above the Fermi energy of electrodes.

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