本論文探討非線性量子點奈米線系統之熱二極體特性分析。我們證實了非線性席貝克效應可以對階梯能階的量子點奈米線有電子熱整流效應，控制量子點奈米線系統的非對稱能階，我們可以在順偏時使得通道傾向共振狀態，反言之，逆偏時則會使通道傾向非共振狀態。一旦我們把聲子熱流考慮進來，會使得整體熱整流比率下降十倍左右。我們發現到熱整流比率可以在考慮矽的能階簡併態時有著顯著提升。除此之外，我們也在非線性量子點奈米線發現負微分熱導的現象，此現象有利應用在熱電邏輯電路以及熱電電晶體上，這對熱電發展是一個重要關鍵。未來，如果我們能夠有效的隔絕聲子，並且所花費的材料成本也夠低，那麼熱電元件會是我們能夠寄望的新元件。

This thesis investigates the nonlinear electron heat transport in quantum dots embedded in nanowires connected to metallic electrodes. It is demonstrated that the nonlinear Seebeck effect can lead to significant electron heat rectification for such a wire with staircase-like energy levels. The asymmetrical alignment of energy levels of QDNWs can be controlled to allow resonant electron transport under forward temperature bias, while they are in off-resonant regime under backward bias. Once taking into account the presence of phonon heat flows, the efficiency of electron heat rectification is suppressed. We find that R will be enhanced by taking advantage of the multi-valley degeneracy of the silicon QD. In addition to this, the behavior of the negative differential thermal conductance is a key ingredient for the implementation of thermal logical gates and transistors..

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