纳米管场发射的电场计算

利用电磁场理论计算出单根纳米管场发射时其尖端附近的电势和电场分布。结果表明 ,纳米管尖端表面电场非常强 ,随着距离尖端表面的距离的增加 ,电场迅速下降 ;尖端附近的场强与纳米管场发射有低的阈值电压相符合。计算还给出在保持极板间距离和电压不变的情况下 ,纳米管长径比越大 ,尖端电场越强 ,因此 ,具有更低的阈值电压

Calculation of Field Emission of Carbon Nanotubes

The spatial distributions of the electric potential and field,near the apex of a single nanotube during the field emission,were analytically calculated on the basis of classical electromagnetic theory.The calculated results show that the electric field strength,very strong near the apex of the tube,drops abruptly with increasing distance and that the field near the apex of the tube agrees well with the fact that the tube has a rather low field emission threshold voltage.With the cathode anode separation and bias voltage unchanged,higher aspect ratio of the carbon nanotube leads to stronger field at the apex and a lower field emission threshold voltage.