High-current THz-band gyrotrons based on axial-slit cavities

We propose a variant of a slotted cavity for high-current gyrotrons based on the coupling of modes with proportional azimuthal indexes and close eigenvalues. A finite-element method simulation is presented, which confirm its high selectivity. 3D PIC simulations of a high-current relativistic gyrotron in the 0.3 THz and 0.5 THz bands with an output power of about 70–80 MW are performed.