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DOE OSTI · 1630485

Cathode Modeling and Diode Performance in a Planar Geometry using Space-charge-limited Emission

Powell, Troy C.
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Abstract

Space-charge-limited (SCL) emission parameters are varied to study the performance effects in a planar diode using an electromagnetic particle-in-cell simulation software suite, EMPIRE. Oscillations in the simulations are found and linked to the emission parameters, namely the breakdown threshold, the emission delay time, and the current density ramp time. The oscillations are suggested to be a transverse oscillator due to the perfect magnetic conductor boundary condition in steady-state operation and the formation of a virtual cathode in the diode driven by the SCL boundary condition.

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Powell, Troy C.. 2020-05-01. Cathode Modeling and Diode Performance in a Planar Geometry using Space-charge-limited Emission. https://doi.org/10.2172/1630485

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