- Open Access
Recent advances in large-signal beam-wave interaction solvers for klystrons
Phys. Rev. Accel. Beams 29, 024801 – Published 20 February, 2026
DOI: https://doi.org/10.1103/s3cg-vnyj
Abstract
A klystron is a microwave vacuum electronic device that converts the kinetic energy of an electron beam into microwave signal energy based on the principle of velocity modulation. Owing to its high peak power, high efficiency, and high gain, the klystron has been widely used in scientific research, national defense, and industrial applications. The interaction between the electron beam and the radio-frequency (rf) field within the resonant cavities, known as the beam-wave interaction, is the core physical process governing klystron operation. A detailed understanding of this process, together with accurate numerical simulation using computational solvers, is essential for optimizing device performance and shortening the development cycle. This paper reviews the large-signal beam-wave interaction solvers commonly used in klystron design and development in mainland China, along with several internationally recognized simulation codes. The discussed solvers cover a range of computational dimensions from one-dimensional (1D) to three-dimensional (3D). Finally, the challenges and future prospects for the development of klystron beam-wave interaction solvers are discussed.
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