Fig. 1. Spectral distributions in k space when the driving laser pulse reaches x = 240 µm for (a) an LS pulse with topological charge varying from l = 3 to l = 9 and total bandwidth Δω = 0.198ω_L0 and (b) an LG pulse with topological charge l = 6 and bandwidth Δω = 0.198ω_L0. The wave number k is normalized to 2π/λ_L0 and the spectral intensity is normalized to the maximum intensity. The SRS signal is marked by the white dotted box.

Fig. 2. Maximum field ratio η_S = E_s/E_L between SRS and driving pulses along the laser propagation direction for cases with different Δω and Δl: black line, LG case ɛ₁ = 0, ɛ₂l_L0 = 0; blue line, LG case ɛ₁ = 0.033, ɛ₂l_L0 = 0; green line, LS case ɛ₁ = 0, ɛ₂l_L0 = 1; red line, LS case of ɛ₁ = 0.033, ɛ₂l_L0 = 1; purple line, super LS case ɛ₁ = 0.033, ɛ₂l_L0 = 1 together with random phases.

Fig. 3. Electron energy spectra when the driving laser pulse reaches x = 240 µm for an LG pulse with topological charge l = 6 and ɛ₁ = 0.033 (black line) and an LS pulse with topological charge varying from l = 3 to l = 9 and ɛ₁ = 0.033 (red line).

Fig. 4. Schematic of the generation of super LS light in a hohlraum at the center of a target chamber, by combining LG beamlets with different frequencies, different topological charges, and slightly different incidence angles, which are produced from Gaussian beamlets by using different phase plates. By controlling the phase and frequency of the LG beamlets via phase plates, we can obtain the following three cases at the observation plane: (a) LS of long pitch, (b) LS of short pitch, and (c) super LS.