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arXiv · 1705.06867

Variation of field enhancement factor near the emitter tip

Debabrata Biswas·Gaurav Singh·Shreya G. Sarkar·Raghwendra Kumar
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Abstract

The field enhancement factor at the emitter tip and its variation in a close neighbourhood determines the emitter current in a Fowler-Nordheim like formulation. For an axially symmetric emitter with a smooth tip, it is shown that the variation can be accounted by a $\cos{\tilde{\theta}}$ factor in appropriately defined normalized co-ordinates. This is shown analytically for a hemi-ellipsoidal emitter and confirmed numerically for other emitter shapes with locally quadratic tips.

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Debabrata Biswas, Gaurav Singh, Shreya G. Sarkar, Raghwendra Kumar. 2017-05-19. Variation of field enhancement factor near the emitter tip. https://doi.org/10.1016/j.ultramic.2017.10.016

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