Evaluation of mode fields in a magnetized plasma waveguide and electron acceleration

Abstract

The fields for the fundamental H10 mode are evaluated in a rectangular waveguide filled with plasma under the effect of external static magnetic field applied along the direction of propagation of the mode (z-axis). In the presence of magnetic field the components Hy and Ex are not suppressed and the mode gets modified. Two-dimensional variations of the mode fields are presented and the effects of magnetic field and plasma density on the cutoff frequency, guide wavelength and the dispersion relation of the mode are studied. It is seen that the guide wavelength gets larger for the higher plasma density and stronger magnetic field; however, it decreases when the waveguide width and the microwave frequency are increased for other fixed parameters. The trajectory of the electron is analyzed under the effects of various parameters, when the electron is injected in the waveguide along the direction of mode propagation. Two cases are discussed when ωp<Ωc and ωp>Ωc. Under such situation, the electron acceleration is also studied and it is observed that the acceleration gradient is increased with the microwave frequency. However, it gets reduced and lower energy gain is obtained under the effect of increasing plasma density and magnetic field.