| Autor: |
Umstattd, R. J., Carr, C. G., Frenzen, C. L., Luginsland, J. W., Lau, Y. Y. |
| Předmět: |
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| Zdroj: |
American Journal of Physics; Feb2005, Vol. 73 Issue 2, p160-163, 4p |
| Abstrakt: |
The fundamental Child-Langmuir limit on the maximum current density in a vacuum between two infinite parallel electrodes is one of the most well known and often applied rules of plasma physics. We develop a simple model using vacuum capacitance, conservation of energy, and conservation of charge to derive the Child-Langmuir space-charge-limited emission. This capacitive model provides physical insight into the origins of the well known (voltage)3"2/(gap distance)2 scaling of the classical current density and does not require the solution of the nonlinear differential equation normally associated with the Child-Langmuir formulation. In addition, the full space-charge-limited solution is reproduced without imposing the condition that the electric field be driven to zero at the cathode surface. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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