Generation of broadband terahertz radiation using a backward wave oscillator and pseudospark-sourced electron beam

Abstract

This paper presents for the generation of a small size high current density pseudospark (PS) electron beam for a high frequency (0.2 THz) Backward Wave Oscillator (BWO) through a Doppler up-shift of the plasma frequency. An electron beam ∼1 mm diameter carrying a current of up to 10 A and current density of 108 A m−2, with a sweeping voltage of 42 to 25 kV and pulse duration of 25 ns, was generated from the PS discharge. This beam propagated through the rippled-wall slow wave structure of a BWO beam-wave interaction region in a plasma environment without the need for a guiding magnetic field. Plasma wave assisted beam-wave interaction resulted in broadband output over a frequency range of 186–202 GHz with a maximum power of 20 W.

W-band klystron upconverter driven by pseudospark-sourced electron beam

“…Following the hollow cathode discharge stage, is the conductive stage, also called the pseudospark discharge stage. Electron beams extracted during the hollow cathode discharge stage have been successfully used to drive a few microwave devices, such as the backward wave oscillator and the extended interaction oscillator [9,10]. It was found that only the electron beam generated during the hollow cathode discharge stage have sufficient energy for the beam wave interaction.…”

Experiments on W-band extended interaction oscillator with pseudospark sourced post-accelerated electron beam

“…7 It was found that the output microwave power is much smaller than the simulated values. A further study shows that the reduction in the radiation power is mainly caused by the beam velocity spread and the current lost during the beam propagating in the beam tunnel.…”

Investigation of millimeter wave extended interaction oscillation using improved pseudospark-sourced electron beams

“…This makes it an excellent electron beam source for desirable compact millimeter wave devices. Among various vacuum electronic devices, the EIO as a linear beam vacuum device has gained considerable attention as a promising millimeter wave oscillation source due to its high gain per unit length and compact configuration [4][5][6][7].…”