The effect of ions on terahertz wave propagation characteristics in plasma sheath

The characteristics of terahertz wave propagation in plasma sheath are studied in this paper, when the effect of ions is considered. Starting from the kinetic equations of particles, the plasma dispersion relation is theoretically derived in the presence of ions and electrons model. Based on the relative permittivity of this dispersion model, the coefficients of power reflection, transmission, and attenuation are calculated for electromagnetic wave propagation in uniform plasma. Numerical simulation is done for relative permittivity and propagation characteristics under different density proportions between ions and electrons. Simulation results show that the influence of ions can be ignored when the proportion is below 10³, and the influence is weak when the proportion is 10⁴. The effect becomes very significant at the same terahertz frequency point when the proportion reaches 10⁵, and the change of power attenuation can reach 200dB. These conclusions could hopefully provide a theoretical reference for the application of terahertz wave to solve the communication blackout problem.