Edge effect on the current-temperature characteristic of thermionic cathodes

  title={Edge effect on the current-temperature characteristic of thermionic cathodes},
  author={Anna Sitek and Kristinn Torfason and Andrei Manolescu and 'Ag'ust Valfells},
We perform a computational study, based on the molecular dynamics method, of the shape of Miram curves obtained from microscale planar diodes. We discuss the smooth transition from the source-limited to space-charge-limited regime due to the finite size of the emitter, i.e. the ”knee” in the Miram curve. In our model we find that the smoothing occurs mostly due to the increased emission at the external edges of the emitting area, and that the knee becomes softer when the size of the emitting… 

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