Field enhancement factor and field emission from a hemi-ellipsoidal metallic needle.

  title={Field enhancement factor and field emission from a hemi-ellipsoidal metallic needle.},
  author={Evgeny G. Pogorelov and Alexander Zhbanov and Yia-Chung Chang},
  volume={109 4},
We present an exact solution for the electrostatic field between a metallic hemi-ellipsoidal needle on a plate (as a cathode) and a flat anode. The basic idea is to replace the cathode by a linearly charged thread in a uniform electric field and to use a set of "image" charges to reproduce the anode. We calculate the field enhancement factor on the needle surface and ponderomotive force acting on the needle. Using the Fowler-Nordheim theory we obtain an exact analytical formula for the total… 

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