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.