Possibilities of efficiency enhancement in cyclotron autoresonance masers (CARMs) due to the use of recovery of the electron energy with a single-step depressed collector scheme are studied. The simple and very clear method of using the phase plane is developed for the analysis of the motion of electrons with different initial velocities in the CARM, operating in various regimes at both fundamental and higher cyclotron harmonics. The total efficiency can exceed 25% for a CARM with a low electron efficiency operating in the regime of electron bunching and 50% for a CARM in the regime of trapping and adiabatic deceleration: of particles. (C) 1997 American Institute of Physics.
- energy recovery
- free electron masers