Abstract
Carbon nanotube (CNT) cold cathodes are proving to be compelling candidates for miniaturized terahertz (THz) vacuum electronic devices (VEDs) owning to their superior field-emission (FE) characteristics. Here, we report on the development of a multi-sheet beam CNT cold cathode electron optical system with concurrently high beam current and high current density. The microscopic FE characteristics of the CNT film emitter is captured through the development of an empirically derived macroscopic simulation model which is used to provide representative emission performance. Through parametrically optimized macroscale simulations, a five-sheet-beam triode electron gun has been designed, and has been shown to emit up to 95 mA at 3.2 kV. Through careful engineering of the electron gun geometric parameters, a low-voltage compact THz radiation source operating in high-order TM 5,1 mode is investigated to improve output power and suppress mode competition. Particle in cell (PIC) simulations show the average output power is 33 W at 0.1 THz, and the beam–wave interaction efficiency is approximately 10%.
| Original language | English |
|---|---|
| Article number | 1768 |
| Journal | Nanomaterials |
| Volume | 9 |
| Issue number | 12 |
| Early online date | 12 Dec 2019 |
| DOIs | |
| Publication status | Published - 12 Dec 2019 |
Keywords
- Carbon nanotubes
- Cold cathode
- Field emission
- High-order mode
- Multi-sheet beam
- Nanotechnology
- Terahertz
- Vacuum electronic devices
ASJC Scopus subject areas
- General Chemical Engineering
- General Materials Science