一維的奈米石墨帶是奈米尺度的石墨切片，它展現了豐富的物理性質。在這篇論文中，我們把焦點集中在空間調製電場作用下的石墨帶電子性質。石墨帶電子性質是由石墨帶寬度與邊界結構所支配(手椅狀和鋸齒狀)，所有的鋸齒狀石墨帶都是金屬性質，手椅狀石墨帶則只有在寬度 N=3I+2 (I是整數) 才是金屬。邊界結構上的差異，造成鋸齒狀石墨帶在費米能上有一部分平坦的能帶。空間調製電場被用來改變這些電子性質上的特性，有關於調製場的週期與強度的效應，將會有詳細的研究。
理論計算上，我們使用單一π鍵結緊束模型，在只考慮最鄰近原子交互作用下去計算能帶結構。根據能帶計算結果，調製電場會破壞能帶簡併度. 改變能帶色散關係. 影響能帶的間距. 改變能隙並造成半導體與金屬之間的轉換。調製電場破壞了鋸齒狀石墨帶，在費米能上部分平坦能帶的簡併度。手椅狀石墨帶在費米能上的線性能帶，則被轉變成拋物線能帶，並有能隙產生。當調製電場的週期與石墨帶的寬度增加時，能帶間彼此距離會縮小以及會有愈多的完全平坦能帶出現。因此大部分的石墨帶其能隙變化，會隨著電場的週期與石墨帶寬度增加而減少。鋸齒狀與金屬型手椅狀石墨帶的能隙則會呈現例外的情況；前者能隙隨著電場強度震盪，後者能隙則是跟石墨帶的寬度無關。
能帶上的變化可以完全的反應在態密度上，外加的電場對於光譜有很大的影響，會改變態密度上第一個發散峰的位置. 影響峰的高度. 平移峰的位置，甚至會產生新的發散峰。這些態密度特徵的變化可以在光學和傳輸實驗中被量測到。

1D nanographite ribbons,or nanoscale graphite fragment, exhibit rich physical properties. In this study, we focus on the electronical properties of ribbons under a spatially modulated electric field. The electronical properties are dominated by the ribbon width and edge structure (armchair and zigzag). All zigzag ribbons are metals, while armchair ribbons are metals only for N=3I+2 (I is integer). There are partial flat bands at Fermi level in zigzag ribbons because of edge structure. A spatially modulated electric field is used to modify the characteristic of the electronical properties. The effects of period and strength are also studied.
To calculate the band structures, the single π-band tight binding method with the nearest neighbour interaction is employed. According to the result of energy bands, the modulated electric field would destroy the degeneracy of energy bands, modify energy dispersions, alter subband spacing, change the energy gap, and cause the semiconductor-metal transition. The field would destroy degeneracy of partial flat bands at Fermi level in zigzag ribbons. Liner bands at Fermi level would be converted into parabolic bands in metallic armchair ribbons. As the period of the field and ribbon width increases, the subband spacing decreases and more completely flat bands are formed. Accordingly the V-dependence energy gap of ribbons is expected to decrease with the increment of the field period and ribbon width. The energy gap of zigzag and semiconducting armchair ribbons are exception. The former is oscillating with field strength; the latter is independent of ribbon width.
The changes of band structures are completely reflected on the features of density of state. The applied field has great influence on energy spectra, namely, changing frequency of first peak, altering peak height, shifting peak position and even producing new peaks. The characteristic could be measured in optical and transport measurements.

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