Theoretical Analysis on Propagation of Electromagnetic Wave in Preformed Narrow Plasma Channel

In the plasma sheath a narrow plasma channel generated by ultraintense laser pulses is simplified as a special cylindrical and hollow plasma waveguide with the infinite thickness of the plasma cladding. The electromagnetic wave (EM) propagation properties of the plasma channel near the cutoff and far from the cutoff are considered. Theoretical analysis shows that TE_0m and TM_0m and hybrid modes emerge in the plasma channel, which is influenced by the normalized frequency parameter B and numerical aperture NA. The cutoffs of the various modes are approximated. Single-mode operation is possible without a high-frequency limitation in the channel.