Abstract
We have developed a three-dimensional nonlinear theory for the slow-wave cyclotron instability in a dielectrically loaded waveguide. The efficiency, gain, and bandwidth of the amplifier are calculated from a self-consistent solution of a set of coupled nonlinear differential equations describing the growth of the electromagnetic field and the evolution of the electron trajectories. Calculations show that very broadband amplification with high efficiency is possible in the slow-wave region of the propagating waves. The instantaneous bandwidth (full width at half maximum) near saturation depends on the efficiency (\ensuremath{\eta}) of the amplifier. For a cold beam, the bandwidth \ensuremath{\Delta}\ensuremath{\omega}/\ensuremath{\omega}\ensuremath{\approxeq}6% at \ensuremath{\eta}\ensuremath{\approxeq}40%, but \ensuremath{\Delta}\ensuremath{\omega}/\ensuremath{\omega} increases to 30% if the amplifier is operated at an efficiency of 20%. The efficiency is very sensitive to the axial velocity spread of the beam since interaction occurs with waves having large propagation constants. The maximum efficiency drops from 48% to 10% as the velocity spread increases from 0% to 5% but the bandwidth shows a small increase.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Physical review. A, Atomic, molecular, and optical physics
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
