Secondary Electron Suppression with Carbonized Aerogels

Abstract

The goal addressed by this project is reduced DC power for high data rate RF communications by increasing the efficiency of traveling Wave Tubes (TWT) for RF communication, which are used by most space missions for communication and radio science at microwave frequencies. The capability needed is a robust electron collector surface with a secondary electron emission lower than ordinary graphite, which is the state of the art. While it is known that replacing a smooth surface with a textured one will reduce secondary electron emission, no robust textured surface is known. Carbonized polyimide aerogels promise the necessary robustness along with reduced secondary electron emission, allowing further improvement of TWT efficiency, achieving a very good return on the low investment made. Aerogels are known to be robust materials, and carbon aerogels are expected to have low secondary electron emission because of their open surface structure. The objective of this proposal is to demonstrate the low secondary electron emission of carbon aerogels and their robustness.