Tunneling of Electromagnetic Pulses Through a Plasma Layer: Numerical Solution of Maxwell's Equations

The article presents the results of numerical modeling of the processes of electromagnetic pulse propagation through media with dispersion, in particular plasma, in the plane wave approximation. The numerical solution of Maxwell's equations is carried out by the finite-difference time-domain method, and the frequency dependence of the medium characteristics is taken into account by introducing an auxiliary differential equation. Spatial-temporal and spectral regularities of transmission and reflection of electromagnetic pulses from plasma layers are investigated. The dependence of the pulse tunneling time on the thickness of the plasma layer, carrier frequency, and duration of the incident pulse is revealed. The pulse tunneling time rapidly tends to the Hartman limit of the Wigner tunneling time with the decreasing of the pulse frequency for a wide range of the pulse duration times.