Frequency control in wake field waveguide structures

The possibility to control the frequency spectrum of Vavilov-Cherenkov radiation in a waveguide accelerator structure with the aid of an external ferroelectric layer is studied. A decrease in the permittivity of a ferroelectric material under the action of an applied electric field leads to an increase in the frequency of the wake radiation field of a relativistic electron bunch. Parameters of the ferroelectric layer are calculated proceeding from the required interval of control of the wake field frequency and the tolerable power losses in the waveguide system. (C) 2002 MAIK "Nauka / Interperiodica".