Title :
Miniature plasma cathode for high-power terahertz sources
Author :
Rodgers, J. ; Chang, R. ; Granatstein, V.L. ; Antonsen, T.M., Jr. ; Nusinovich, G.S. ; Carmel, Y.
Author_Institution :
Inst. for Res. in Electron. & Appl. Phys., Maryland Univ., College Park, MD, USA
Abstract :
Efforts to improve efficiency in terahertz vacuum electronic sources such as backward-wave oscillators (BWO) have motivated studies of cathodes capable of generating high-density electron beams so that various interaction circuits may be driven closer to saturation. Preliminary results from experiments on a miniature plasma cathode demonstrate that current densities of up to 1 kA/cm2 in a 100-micron diameter beam have been achieved. Initial analysis of a 850-GHz, slotted slow-wave structure show that the circuit could be driven at 3-4 times the starting current and that efficiencies of a few percent could be realized. Tests on a gridded plasma cathode show that stable beams of 200 mA at a pulse length of 100 μsec and repetition frequencies of up to 200 Hz were generated.
Keywords :
backward wave oscillators; cathodes; current density; optical saturation; submillimetre waves; 100 micron; 850 GHz; backward-wave oscillator; current density; driver saturation; high-density electron beam; high-power terahertz source; interaction circuit; miniature plasma cathode; slow-wave structure; terahertz vacuum electronic source; Cathodes; Circuit testing; Current density; Electron beams; Frequency; Oscillators; Particle beams; Plasma density; Plasma sources; Plasma stability;
Conference_Titel :
Infrared and Millimeter Waves and 13th International Conference on Terahertz Electronics, 2005. IRMMW-THz 2005. The Joint 30th International Conference on
Print_ISBN :
0-7803-9348-1
DOI :
10.1109/ICIMW.2005.1572539