串接耦合量子點之熱電特性

Thermoelectric Properties of Double Quantum Dots Embedded in a Nanowire

花銘遠(Ming-Yuan Hua)

指導教授 ： 郭明庭

國立中央大學/資訊電機學院/電機工程學系/碩士(2011年)

摘要

為了瞭解量子點間電子躍遷強度、量子點間庫倫交互作用以及量子點大小變動對熱電特性的影響。我們利用雙能階安德森模型(Two Level Anderson Model)模擬雙量子點崁入奈米線的系統，並討論其熱電特性。其中雙能階安德森模型中包含量子點間電子躍遷、量子點內庫倫交互作用以及量子點間庫倫交互作用。庫倫阻斷情況下的熱流與電流可以利用凱帝旭格林函數的方法(Keldysh-Green’s function technique)計算得知。接著探討此系統在線性響應區間的電導、Seebeck coefficient、熱導以及ZT值。我們發現庫倫交互作用和量子點大小不一致都會抑制ZT值，但量子點間庫倫交互作用強度在大於某個程度後此效應卻幾乎不影響ZT值。

關鍵字

串接耦合量子點之熱電特性

並列摘要

In order to investigate the influence of electron hopping, interdot Coulomb interaction, and size fluctuation on thermoelectric properties. We simulate thermoelectric properties of double Quantum Dots embedded in a nanowire by a two-level Anderson model which including electron hopping, intradot Coulomb interactions and interdot Coulomb interactions. The charge and heat currents in the Coulomb blockage regime are calculated by Keldysh Green''s function technique. The electrical conductance, Seebeck coefficient, electronic thermal conductance, and figure of merit (ZT) of the system are calculated in the linear response regime. We find that the figure of merit ZT is markedly reduced by the size fluctuation and Coulomb interactions.

並列關鍵字

Thermoelectric Properties of Double Quantum Dots

參考文獻

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