Fig. 1. Schematic diagram. (a) Schematic diagram of the experimental setup; (b) experimental setup for recording ultrasonic signal induced by filament; (c) experimental setup for recording the cross section of filaments; (d) time-domain diagram of the filament-excited ultrasonic signal; (e) longitudinal acoustic intensity along the filament without turbulence (dashed line is 3σ).

Fig. 2. (a) Onset position and (c) length of filaments as a function of turbulence refractive index structure constant within the 30 m region; (b) onset position and (d) length of filaments as a function of turbulence region; (e) schematic of turbulent regions and femtosecond lasers.

Fig. 3. (a) Dependence of standard deviation of transverse displacement of the filament on the turbulence refractive index structure constant in 30 m region; (b) dependence of standard deviation of transverse displacement of the filament on the turbulence region with C_n² = 2.5 × 10⁻¹¹ m^−2/3.

Fig. 4. (a) Dependence of diameter of filament on turbulence refractive index structure constant in 30 m region; (b) dependence of intensity of filament on turbulence refractive index structure constant in different regions; (c) shapes of the filament cross sections corresponding to numbers in (a).