Analysis of a 0.6-THz Second Harmonic Gyrotron With Gradually Tapered Cavity

The mode competition and beam wave interaction in a gradually tapered cavity are studied for achieving high efficiency of a 0.6-THz second harmonic (SH) gyrotron. In order to obtain high power and stable radiation, the TE32,5 mode is selected as the operating mode of the desired gyrotron to realize a single-mode oscillation. The issues of studying the high-order mode gyrotron are solved effectively by transforming the generalized telegraphist's equations. The efficiency and the output power of the gyrotron under different conditions have been calculated by the code, which is based on the transformed equations. The results show that a single-mode SH radiation with a power of over 100 kW at frequency of 0.6 THz could be achieved.