Title :
Millimeter-wave radiation generated via plasma three-wave mixing using high-current density counter-streaming electron beams
Author :
Santoru ; Schumacher
Author_Institution :
Hughes Res. Lab., Malibu, CA, USA
Abstract :
Summary Form only given, as follows. Electron-beam-excited, counterpropagating electron plasma wave (EPWs) interact nonlinearly through the plasma three-wave mixing process to generate electromagnetic radiation at twice the plasma frequency. Radiation saturation is not observed up to beam current densities of 2 A/cm/sup 2/, where the peak power is 8 kW. To investigate the saturation mechanism and maximize the radiation generation efficiency, plasma-cathode electron beams, which can provide up to 20 A/cm/sup 2/ at 30 kV, have been installed. The counterpropagating EPW topology required for three-wave mixing was created using a single high-current-density electron beam by means of a backscattering process. When the background plasma was generated by electron-beam-gas impact ionization, the current density threshold for single-beam radiation emission was about 12 A/cm/sup 2/. Scaling experiments have explored the two-beam and single-beam radiation generation processes.<>
Keywords :
backscatter; electromagnetic wave propagation in plasma; plasma density; plasma diagnostics; plasma transport processes; plasma waves; 8 kW; backscattering process; electron-beam-gas impact ionization; high-current density counter-streaming electron beams; microwaves; millimeter-wave radiation generation; nonlinear interaction; plasma frequency; plasma three-wave mixing; plasma-cathode electron beams; radiation saturation; saturation mechanism; scaling experiments; single-beam radiation emission; Charge carrier processes; Electromagnetic propagation in plasma media; Plasma measurements; Plasma properties; Plasma waves;
Conference_Titel :
Plasma Science, 1989. IEEE Conference Record - Abstracts., 1989 IEEE International Conference on
Conference_Location :
Buffalo, NY, USA
DOI :
10.1109/PLASMA.1989.166239
