Generation of pulsed terahertz radiation in a relativistic gyrotron in the frequency multiplication mode

Within the framework of the averaged approach, the frequency multiplication mode in a relativistic gyrotron in the 300 GHz range was studied. It is shown that under conditions of selective excitation of oscillations on the ТЕ33,2 mode at the fundamental cyclotron harmonic, it is possible to generate radiation with a frequency of 1.5 THz and a power of up to 1.5 kW on the ТЕ165,7 mode with excitation of the fifth harmonic of the gyrofrequency. A three-dimensional simulation of the gyrotron by the large particle method was performed, on the basis of which a narrowing of the generation zone at the main cyclotron harmonic was shown in comparison with that calculated within the framework of a simplified model, which leads to a limitation of the power of terahertz radiation at the level of 200 W.