本論文理論性地探討單顆量子點崁入具低熱導率的奈米線，此奈米線外接電極，並計算其電導、熱導、熱電係數以及熱電優值(ZT)。我們利用多能階的安德森模型(Anderson model)來模擬單量子點傳輸的情形，在庫倫阻斷區域之電流與熱流公式可經由Keldysh Green function技術的推導而得。電子聲子交互作用產生的非彈性散射、缺陷和量子點大小的變化都將會明顯得抑制ZT值。而為了增加ZT值，降低晶格熱導是非常重要的。此外我們也發現調控閘極偏壓所造成的能階偏移對系統的ZT值影響很大。

This thesis theoretically studies the electrical conductance, thermal conductance, thermal power, and figure of merit (ZT) of a single quantum dot (QD) embedded into a nanowire with low heat conductivity connected to electrodes. The multilevel Anderson model is used to simulate this quantum dot junction system. The charge and heat currents in the Coulomb blockade regime are calculated by the Keldysh Green function technique. The ZT values are seriously suppressed by the inelastic scattering effect arising from electron-phonon interactions, defects and QD size fluctuation. In the optimization of ZT, the reduction of lattice thermal conductance is important to enhance ZT values. We find that the system ZT values are sensitive to the detuning energy, which can be controlled by the gate voltage.

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