Simulation Study of Annular Beam Electron Optical System Based on Carbon Nanotube Cold Cathode

Carbon nanotube (CNT) cold cathode has become an excellent candidate material for terahertz (THz) vacuum microelectronic radiation source due to its excellent field emission characteristics. Here, we report the development of an annular beam CNT cold cathode electron optical system. Through parametrically optimized macroscale simulations, the cold cathode electron optical system based on CNT film emitter has been demonstrated to emit up to 85.8 mA circular electron beam at a bias of 14.8 kV, with a high beam current density of 156 A/cm ² .