Focusing Magnetic Field Effect on Wave Dynamics In Plasma-Beam Superheterodyne FEL of Dopplertron Type with Rectilinear REB

This paper presents an investigation of the focusing magnetic field effect on amplification characteristics of the plasma-beam superheterodyne free electron laser of dopplertron type with rectilinear relativistic electron beam. We have analyzed the saturation levels and the rates of the signal electromagnetic wave for different magnetic field intensity values. The device operation mode with the maximum level and gain rate have found. The results demonstrate that the use of the focusing magnetic field contribute to the increase of electromagnetic terahertz range radiation amplification in the studied device.