Accession Number : AD0456769

Title :   STABILITY AND RF BEHAVIOR OF PLASMA DIODES.

Descriptive Note : Technical rept.,

Corporate Author : STANFORD UNIV CA STANFORD ELECTRONICS LABS

Personal Author(s) : Holmstrom, F. R.

Report Date : AUG 1964

Pagination or Media Count : 109

Abstract : Interpenetrating streams of cold electrons and ions injected from opposite parallel-plane electrodes or grids give rise to various dc potential distributions, depending on the boundary conditions. The rf impedance and the stability of the dc states are investigated theoretically. Two coupled second-order inhomogeneous collisionless space-charge-wave equations, one for electrons and one for ions, are solved numerically. The rf impedance is thus computed and used to investigate stability. It is found that: the diode is stable if either or both emitters are spacecharge limited or temperature limited; the rf impedance is inductive for frequencies below the ion plasma frequency if both emitters are spacecharge limited, but capacitive if either emitter is temperature limited, and instabilities of the Birdsall and Bridges type arise if either electrons or ions are injected into a retarding field, although the calculated resistance is still found to be positive for real frequencies. Experiments were performed on cesium plasma diodes, and the rf impedance measured when the diodes were heavily dc biased. Measured impedance characteristics corresponded most closely to the theoretical case with space-charge-limited electrons and temperature-limited ions. (Author)

Descriptors :   *DIODES, PLASMA SHEATHS, ELECTRONS, IONS, IONIZATION, VOLTAGE, ELECTRODES, STABILITY, RADIOFREQUENCY, ELECTRICAL IMPEDANCE, EQUATIONS, SPACE CHARGE, TEMPERATURE, INDUCTANCE, INJECTION, ELECTRICAL RESISTANCE, CESIUM, ELECTROSTATIC FIELDS.

Distribution Statement : APPROVED FOR PUBLIC RELEASE