Emission gated device issues

A review of linear and nonlinear analyses applicable to emission gated devices is provided with an explicit declaration of the physical assumptions for each model. The authors consider density gating, not velocity modulation, emphasizing high-power and high-efficiency applications. Increased efficiency through the use of density gating for the RF input bunching of an electron beam is expected. The authors review the basic dynamics of bunch formation and describe the gating technologies currently available for the production of a prebunched beam. Considerable insight into the basic physics of emission gating, such as beam dynamics and frequency spectra, is obtainable from numerical modeling. Some unresolved issues are presented for investigation.