Carbon Nanotube Based Electron Field Emission Cathodes for Traveling Wave Tubes

The conventional thermionic cathodes used in traveling wave tubes (TWTs) suffer from many technical limitations including limited current density, poor energy efficiency, difficulty of control, and lack of miniaturization. Xintek, Inc. has developed proprietary technologies for fabrication of high performance field emission cold cathodes based on carbon nanotubes (CNTs). Our CNT cathodes tested at Air Force have shown high emission current density (up to 75 A/cm2), excellent emission stability, and high pulsation rate (>100 KHz). They have great potential to replace the thermionic cathodes and provide enhanced TWT performances. In this Phase I project we will: a) study and refine the performance of our CNT cathodes to generate current densities of 1-10 A/cm2, the typical performance of thermionic cathodes used in TWTs; b) collaborate with the Beverly Microwave Division (BMD) of Communications & Power Industries (CPI) to investigate the performances of our CNT cathodes in practical TWT environments and predict current density of our cathodes in real TWT devices. In phase II we will: a) integrate our CNT cathodes into actual TWTs and optimize the cathode design to enhance their efficiency, reliability and current density; b) prepare a commercialization roadmap to market the technologies.