Guiding performance of 6 GHz electromagnetic wave by single laser plasma filament

Abstract

The guiding of a 6 GHz electromagnetic (EM) wave along a plasma filament produced by intense femtosecond laser pulses is investigated with the electromagnetic simulation software XFDTD. The results confirm that the plasma filament can guide the EM wave over a long distance, with low attenuation relative to freely propagating the signal. Furthermore, the filament can change the phase wavelength of the signal in the waveguide. Also notable is that the power density of the wave along the filament monotonically decreases with increasing EM wave propagation length. The wavelength of the EM wave along the plasma filament is about 4.98 cm, which is slightly less than that of the incident 6 GHz signal, i.e., the wave velocity along the filament is less than the speed of light.