Ch.Z. Nguyen¹, S.A. Alikov²,  A.G. Shein³, D.G. Kovtun4, E.M. Ilyin5

1-4 Volgograd State Technical University (Volgograd, Russia)

5 Moscow State Technical University. N.E. Bauman (Moscow, Russia)

Mastering the terahertz range promises many opportunities for practical application, in this regard, the problem of optimizing existing and creating new amplifiers and generators operating in this frequency range does not lose its relevance. One of the possible approaches for solving the problem under consideration is provided by electrovacuum electronics, where a traveling wave lamp can be especially noted due to the combination of its characteristics in terms of power and bandwidth. Goal. Creation of a threedimensional model of the device, based on the finite difference time domain (FDTD) method for Maxwell's equations and the cloudin-cell (CIC) method, followed by a series of numerical experiments to study the characteristics of the device with the given electron flow parameters and space configuration interactions. Results. The results of modeling a traveling-wave tube of the O-type in the terahertz range are presented using the example of an amplifier with a retarding structure of the double comb type with a strip electron flow. It is shown that the presented algorithm can be used to simulate processes in a slow-wave structure of a complex type with an input and output waveguide and absorber inserts. The power gain is estimated for a system with an absorber of various lengths, and the absorber length is optimized. Practical significance. The field of application of the proposed model is the study of processes in electrovacuum devices with the aim of both modernizing existing microwave amplifiers and generators in the terahertz range, and developing new devices.

Nguyen Ch.Z., Alikov S.A., Shein  A.G., Kovtun D.G., Ilyin E.M. Three-dimensional modeling of processes in a traveling-wave tube terahertz range. Electromagnetic waves and electronic systems. 2021. V. 26. № 1. P. 45−54. DOI: https://doi.org/10.18127/j15604128-202101-05. (in Russian)

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