Multimode Characteristics of Space-Charge Waves in a Plasma Waveguide

The multimode characteristics of the space-charge wave are investigated in a cylindrical waveguide complex plasma. The dispersion relation of the space-charge wave is derived in a waveguide, including two-temperature electrons. The results show that the wave frequencies in a plasma with a high population of high-temperature electrons are always smaller those in a plasma with a low population of high-temperature electrons. It is also found that the population of high-temperature electrons suppresses the group velocity of the space-charge wave. In addition, it is found that the frequency increases with an increase in the radius of the cylindrical wave guide. The variations of the frequency and the group velocity due to the density, temperature, and geometric effects are also discussed.