Operating characteristics of modes in an A6 relativistic magnetron with a stepped cavity

Summary form only given. The possibility of using a one-step cavity to replace the common tapered cavity to extend the interaction volume to enhance the beam-wave interaction in an A6 relativistic magnetron with axial extraction for ease of manufacture for future experiments is studied using the particle-in-cell (PIC) code UNIPIC. In the stepped cavity A6 relativistic magnetron driven by a transparent cathode, the efficiency can be as high as 78% with GW output power in optimized configurations. When a voltage of 400 kV is applied, the PIC simulations show that the energetic electrons emitted from the cathode strike the anode block wall such that secondary electron and backscattering electron emission occur.