Effect of Magnetic Field on the Propagation Characteristics of EM Waves in Plasma Filaments Layer with a Three-Layer Circular Structure

The effect of magnetic field on the propagation characteristics of electromagnetic (EM) waves in a plasma filaments layer with a three-layer circular structure generated by femtosecond laser was studied. To simulate the propagation characteristics of plane EM waves with plasma parameters and filament array in a magnetic field, the current density convolution finite difference time-domain method was used. The simulation results show that the decrease in transmittance (peaks) at certain frequencies in the presence of an external magnetic field is obvious, and even at small electron number densities, the transmittance can be reduced with the filament array. In the absence of a magnetic field, the peaks and valleys in the considered frequency bands (f=1~100GHz) are repeated periodically at 30GHz intervals. However, in the presence of a magnetic field, when the layer-to-layer distance is large, they vary to a maximum of 20GHz interval in the f>50GHz band.