A computational efficient simulation tool for gyrotrons

A device-specified in-house code for gyrotron simulation is reported. By assuming that the gyrotron being in the steady oscillation state, the beam-wave interaction in the gyrotron cavity can be approximated by the telegraphist´s equations together with the Lorentz force equations. Then, by incorporating cut-off and open boundary conditions at the input and output ends of the cavity separately, the above differential equations can be solved numerically. This algorithm is more computational efficient than the Particle-In-Cell (PIC) approach in theory. The self-developed code is then verified by the agreement with 3D PIC code.