設計熱流二極體，對熱流的控制應用是非常重要的。然而，整個領域的進展非常有限。特別是，少有實驗的文獻在期刊刊出。雖然理論在相同課題有不少的報導，但是理論文獻所提出的系統及熱整流的機制，對實驗的建構是非常困難的。所以對實驗的幫助還是很有限，而多數的熱整流二極體都採用聲子為主要的熱流載子。本論文考慮電子為熱流整流的主要載子。量子點奈米線因可以大大增加聲子的散射，所以聲子熱流可以被壓抑。利用非均勻的量子點奈米線所形成的階梯能階，我們可以對電子熱流產生效能不錯的熱整流特性。相較其他的文獻所提出的設計，量子點奈米線或許是一個較容易建構的系統。

It is very important to design novel heat diodes in the control of heat currents. So far, few literatures have experimentally reported the heat rectification feature of such devices. Although some theoretical concepts considering phonon carriers to carry heat currents have been proposed to design heat diodes, these proposals are not easy to be implemented by experiments. This thesis considers the structure of quantum dot superlattice nanowires with staircase energy levels and theoretically demonstrates that electron heat currents show a heat rectification behavior. To have a high efficient electron heat diode, phonon heat currents should be fully blocked.

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