Development of Middle-Power W-Band Gyrotron in IAP RAS

In the last few years, gyrotron and other gyrodevises complexes based on “warm” magnets that do not require cooling to liquid-helium temperatures have been successfully created and investigated at many institutions [1]-[4]. A further step to improve the operation of such complexes is the development and design of gyrotrons operating on gyrofrequency harmonics. However, for such systems, the problem of selection of the working type of oscillations is exacerbated, especially when using oversized resonators whose ohmic losses are much lower than in the case of modes with relatively small indices. At present, a number of methods are proposed that provide high selection, both with the help of electron-optical systems and with the use of noncanonical electrodynamic systems. In this work, investigation the possibilities of using non-traditional electrodynamic systems with annular diaphragm to increase the selectivity of the working type of oscillations was done. Based on the results of the work, it is planned to develop the electrodynamic system for a W-band gyrotron operating on the third harmonic (in this case solenoid with water or oil cooling, which costs much less than a cryomagnet can be used).