Maximum time-dependent space-charge limited diode currents

Griswold, M. E.; Fisch, N. J.

doi:10.1063/1.4939607

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Maximum time-dependent space-charge limited diode currents

Griswold, M. E.·Fisch, N. J.

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Abstract

Recent papers claim that a one dimensional (1D) diode with a time-varying voltage drop can transmit current densities that exceed the Child-Langmuir (CL) limit on average, apparently contradicting a previous conjecture that there is a hard limit on the average current density across any 1D diode, as t → ∞, that is equal to the CL limit. However, these claims rest on a different definition of the CL limit, namely, a comparison between the time-averaged diode current and the adiabatic average of the expression for the stationary CL limit. If the current were considered as a function of the maximum applied voltage, rather than the average applied voltage, then the original conjecture would not have been refuted.

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70 PLASMA PHYSICS AND FUSION TECHNOLOGY CURRENT DENSITY CURRENTS ELECTRIC POTENTIAL ELECTRODES ONE-DIMENSIONAL CALCULATIONS SPACE CHARGE TIME DEPENDENCE VOLTAGE DROP

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Griswold, M. E., Fisch, N. J.. 2016-01-15. Maximum time-dependent space-charge limited diode currents. https://doi.org/10.1063/1.4939607

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