A 0.2-THz coaxial-waveguide gyrotron traveling-wave amplifier

Mode competition is a severe problem in the development of a high-power gyrotron traveling-wave-tube (gyro-TWT) amplifier in terahertz (THz) region. To improve the stability of this device, this paper investigates the possibility of using a coaxial waveguide with distributed losses as the interaction structure of a 0.2-THz gyro-TWT. Under stable operating conditions, the achieved performance of the gyro-TWT amplifier, including the output power, efficiency, gain and bandwidth, are predicted.