Computer simulation studies of cylindrical MILO microwave sources

Summary form only given. Simulation studies of cylindrical MILO (magnetically insulated transmission line oscillator) devices have been performed. The simulations were performed using VENUSRZ, a 2-D relativistic electromagnetic particle-mesh program. The main focus of the simulation studies has been an investigation of the effect of variation of the MILO and loading circuit parameters on the efficiency of power extraction. A number of single-cavity and multicavity power extraction schemes were investigated. Poor efficiencies (~1%) often occur even when the MILO configuration oscillates strongly; however, minor changes are able to convert these efficiencies to over 10% for single-cavity power extraction, with a further doubling for multicavity extraction. Efficient single-cavity extraction needs a large electromagnetic power flow to the output cavity, namely a finite group velocity, ν, whereas the typical MILO structure encourages oscillation near the π mode where ν is zero