Chong-Zu Nguyen1, D.G. Kovtun2

1,2 Volgograd State Technical University (Volgograd, Russia)

2 kdmob74@gmail.com

In an O-type traveling-wave tube (TWT), part of the electromagnetic wave energy can propagate back to the input during the amplification process, which leads to unstable operation of the device. To prevent this effect, an absorber can be used in the device that absorbs the reflected wave energy and protects the input and output powers from fluctuations. This paper presents numerical simulation results of processes in a full terahertz TWT model using an absorber based on the finite-difference time-domain method to solve Maxwell equations and the particle-in-cell method to calculate electron beam dynamics. Obtained data analysis makes it possible to clearly demonstrate the effect of absorber on TWT wave amplification in single-frequency mode.

Nguyen Chong-Zu, Kovtun D.G. Effect of absorber characteristics on O-type traveling wave tube operation. Electromagnetic waves and electronic systems. 2024. V. 29. № 1. P. 30−40. DOI: https://doi.org/10.18127/j15604128-202401-03 (in Russian)

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