Vacuum electron tubes for THz applications

Vacuum devices, such as TWTs and BWOs, for THz regime, represent a new challenge in vacuum electronics. Structures with dimensions in the range of microns are required to optimize the energy transfer from an electron beam to the RF field. The availability of codes to accurately analyze micro slow-wave structures at THz frequency is fundamental for a reliable and fast design. A procedure to design a THz backward-wave oscillator based on an analytical code to compute the cold parameters in backward-wave mode and 3-D electromagnetic codes for device performance is presented. An output power of 190 mW is demonstrated at 1027 GHz.