本論文探討一維的量子點超晶格奈米線系統應用在熱引擎的分析。由於超晶格奈米線會降低聲子熱導，在能量收集的應用中極具潛能，但是許多的研究都是關於相同能階的奈米線，而且不考慮負載效應，在這裡我們提出了一種階梯式能階的超晶格奈米線應用在熱引擎，並且考慮負載的感應熱電壓，利用非線性席貝克效應控制奈米線中的非對稱能階排列，讓通道在順偏時傾向共振狀態，在逆偏時則具有非共振狀態，使其具有與方向相依的輸出功率及熱電流。在這種機制下，發現階梯式能階超晶格奈米線的功率輸出及效率都會優於相同能階的超晶格奈米線。除此之外，熱引擎也具有熱二極體的功能，可以表現出顯著的熱整流比率，而在開路條件中會發現負微分熱導的現象，有利應用於熱電邏輯電路及熱電電晶體。

This paper discussed the one-dimensional quantum dot superlattice nanowire(SLNW) heat engine(HE) due to reduction of the phonon thermal conductance.Many efforts have been devoted to the SLNW with uniform energy level and neglect the external loading effect. Here we propose a heat engine made of SLNW with staircase-like quantum dot energy levels and consider the induced thermal voltage of the load.The nonlinear Seebeck effect is used to control the alignment energy level in the nanowire and allow resonant electron transport under forward temperature bias, while they are in off-resonant regime under reverse temperature bias. Under this mechanism, the power output and efficiency of such a SLNW are better than SLNWs with uniform QD energy levels. In addition, the HE has the the functionality of a heat diode with impressive negative differential thermal conductance under open circuit condition, which is beneficial to thermoelectric logic circuits and thermoelectric transistors.

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