本研究主要以非平衡態分子動力學模擬方法探討奈米碳材之特異熱傳行為，主要分成兩部分，分別為石墨烯聲子晶體之同調傳輸現象以及奈米碳管之非局部效應。石墨烯聲子晶體是於石墨烯上建立週期性空孔而成，此結構可有效降低材料之熱傳導係數，並且可用來操控波傳行為，當在材料上製造週期性的孔洞時，在孔隙率不變的條件下，其熱傳導係數會隨單位晶格尺寸變小而降低，然而當單位晶格尺寸縮小至某一臨界值時，其熱傳導係數反而會上升，此現象即為同調傳輸。而非局部效應則是相鄰兩熱源間的熱傳行為會被第三端熱源所影響，且此現象在巨觀下是無法觀察到的。
同調傳輸研究中，會先將石墨烯週期性挖等腰三角形孔以製作成聲子晶體，探討單位晶格長度、三角形空孔之轉角、自由層長度、系統溫度以及週期排列方式對同調傳輸的影響；而在非局部效應中，首先建立扶手椅型奈米碳管，並會在其兩端設置控溫層，在中間的部分會設置一熱流注入區，改變熱流大小、注入熱流之位置、兩端控溫區之溫差、自由層長度等，觀察是否具非局部效應。
於同調傳輸發現，等腰三角形空孔之週期排列石墨烯聲子晶體中可觀察到同調傳輸現象，而單位晶格長度、三角形空孔之轉角、自由層長度、系統溫度以及週期排列方式，皆會影響石墨烯聲子晶體之熱傳導係數，且同調傳輸較容易出現於系統溫度為200K之石墨烯聲子晶體中，並於特定的三角形空孔轉角發現對於同調傳輸有抑制的效果，而聲子相關性之分析中發現不同的單位晶格長度下，有著不同的熱傳機制，當單位晶格較小時，熱傳主要由x方向之低頻聲子所貢獻，但當單位晶格長度變大時，出平面方向之聲子模態開始主宰石墨烯聲子晶體之熱傳。於奈米碳管之非局部效應發現，注入熱流之大小、注入熱流所覆蓋之範圍及注入熱流之位置對於非局部效應影響甚小，僅改變自由層長度可觀察到非局部效應有較明顯的改變。

In this study, the coherent transport in graphene phononic crystal and nonlocal effect in carbon nanotubes (CNTs) were investigated by using non-equilibrium molecular dynamics simulation method.
In the study of coherent transport in graphene phononic crystal, phononic crystal of isosceles triangular holes were created, and different lengths of unit cell were set to investigate the phenomenon of coherent transport. Furthermore, the rotate angles of isosceles triangular holes, system temperature, the length of free slab, and period arrangement were also varied to explore their effects on the coherent transport, then phonon correlation and dispersion curve would be used to analyze the result of simulation. In the study of nonlocal effect in CNTs, CNTs with charity of (6, 6) were created, the length of free slab, temperature difference, the rate of injection heat flow, the coverage area of injection heat flow and the position of injection heat flow were varied to investigate the effects on nonlocal effect, then Landauer-Büttiker formula would be used to quantify nonlocal effect, and study would also analyzed the heat flow to further understand the mechanisms of nonlocal effect.
In the study of coherent transport in graphene phononic crystal, coherent transport could be observed in period arrangement graphene phononic crystal with isosceles triangle holes, however, when system temperature enhanced to 300K, coherent transport would be inhibited, and both phonon correlation and dispersion curve could be used to predict the quantity of thermal conductivity. In the study of nonlocal effect in CNTs, the effects of the rate, the coverage area ,and the position of stable heat flow are very small, only the length of free slab has higher influence on nonlocal effect.

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