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A traveling wave tube (TWT) based on carbon nanotube (CNT) cold cathode is theoretically researched in this paper. A magnetic injection electron gun and helix slow-wave structure is adopted in the TWT. Simulation results show that the maximum output power of the CNT TWT can reach 54 W at 9.4 GHz with an input power of 50 mW, corresponding to the maximum gain of 30 dB, when the gyrating electron beam...
A gridded micro-focus X-ray electron gun based on carbon nanotube cathode has the advantages of small volume, clear imaging and high temporal resolution compared with the conventional X-ray source. An array of CNT bundle is simulated to reduce the electric field screening effects for achieving stable large current density. The gridded electron gun based on carbon nanotube cathode is simulated by three-dimensional...
High power terahertz (THz) sources and amplifiers hold the potential to greatly improve remote sensing and high bandwidth communication. To enable these applications, a Traveling Wave Tube (TWT) operating at 0.22 THz and a multi-cathode Field Emission (FE) electron gun are developed and characterized using a Particle-in-Cell simulation. Three candidate high current density cathode materials, Halfnium...
We present the first steps for the validation of a field emission array (FEA) adapted to the modulation of electron beams at THz frequencies. This specific cathode relies on the coupling of an infrared dual-frequency laser (Deltaf~1THz) with a field emitter array composed of Multi-Wall Carbon Nanotubes. Thanks to the pre-modulation of the electronic beam, increased powers are expected for the Traveling...
We have studied two different kinds of electron tubes using a cold field emission cathode as the electron source. This cathode is an array of vertically aligned multiwall carbon nanotubes. The first device is a triode. With this device, we demonstrated the modulation at 32 GHZ of a 1.4 A/cm2 peak current density with a 82% modulation ratio. The second device is a traveling wave tube. For this device,...
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