Fig. 1. Schematic of formation of femtosecond laser filament[9]

Fig. 2. Schematic of electromagnetic wave transmission via single channel[38]

Fig. 3. Schematic of monitoring plasma produced by laser guiding of high-voltage discharge[39]

Fig. 4. Schematic of experimental setup for single filament microwave coupling[40]

Fig. 5. Experimental setup for multi-filament plasma microwave energy transmission[41]

Fig. 6. Schematic of electromagnetic wave transmission via double-channel femetosecond laser plasma[42]

Fig. 7. Initial intensity distribution of ring laser beam with modulation[46]

Fig. 8. Model of hollow core plasma waveguide[48]

Fig. 9. Model of plasma filament waveguide. (a) Initial intensity distribution of femtosecond laser beam; (b) cross section of three-ring waveguide structure; (c) cross section of single filament[49]

Fig. 10. Relationship between real part of wave number of surface wave and electron density. (a) v=109 Hz; (b) v=1010 Hz; (c) v=1011 Hz; (d) v=1012 Hz

Fig. 11. Relationship between imaginary part of wave number of surface wave and electron density

Fig. 12. Electric field distributions at different times. (a) t=8 ns; (b) t=33 ns; (c) t=68 ns

Fig. 13. Electric field signals at different positions. (a) z=2 m; (b) z=8 m