Microwave excitation and amplification using cyclotron interaction with an axial electron velocity beam
(EN)
Vomvoridis, JL
(EN)
Iatrou, CT
(EN)
This paper addresses the stability in an electron-cyclotron maser of a filamentary mono-energetic electron beam with axial initial electron velocity interacting with fast hybrid waves in a partially dielectric-loaded cylindrical waveguide. This interaction is shown to lead to a convective instability when the transverse magnetic force on the beam electrons exceeds the corresponding electric force component. The dispersion relation for the coupled waveguide-cyclotron beam modes is obtained using Maxwell's fluid equations. Solutions of this relation are obtained which lead to expressions for the temporal growth rate and the gain per unit length. The potential application of this instability for the design of a millimetre amplifier is also assessed.
(EN)
