Using the 2.5-Dimensional PIC Code for Simulating Gyrotrons with Nonsymmetric Operating Modes

Modeling of gyrotrons by the particle-in-cell (PIC) method usually requires three-dimensional simulation. For large parameters of the oversized interaction space, this entails rather long calculation times. This work shows that one can reduce the dimension of the problem and employ 2.5-dimensional PIC simulation under certain conditions. Using a gyrotron with an operating frequency of 170 GHz and operating mode TE 28, 12 as an example, the influence of an external signal on the output-radiation spectrum in the presence of accelerating-voltage fluctuations is studied