Group Time Delay of Ultrashort Radio Pulse Propagating Through Plasma Layer

This article addresses the problem of determining group delay time for an ultrashort radio pulse travelling through a medium with negative permittivity and given frequency dispersion. The medium simulates a layer of collisionless plasma while ignoring the movement of positive ions. The study investigates signal generation in the time domain for a 0.2 ps duration radio pulse with a filling frequency of 5 THz passing through a plasma layer at frequencies of 2.5 and 7.5 THz. Spectra of the transmitted pulse were computed, and the impact of dielectric constant on group delay was evaluated. The problem was modelled using the impedance analogue approach of electromagnetic space proposed by Shchelkunov-Sestroretsky. The first part presents the geometry of the problem studied, which is modelled using Tamic Planar Rt-H Analyzer software. In the second part, amplitude and phase spectra of an ultrashort terahertz radio pulse transmitted through a collisionless plasma layer were calculated. The study determined the effect of the plasma layer on group delay (GD), which is a complex parameter used to measure distortion of an ultrashort terahertz radio pulse.