Figure 7.

Multi-pulse saturation behaviour of an ablated dimple. (a) The ablated depth of dimple dependence on a number of pulses per spot. Solid dots - experimental data points at different peak laser fluence values, solid line - fit by Equation (11) with N₀ = (1.0 ± 0.1) × 10³, ΔN = (2.0 ± 0.2) × 10² and δ(1) ≈ 50 ± 5 nm. (b) Ablation depth per pulse dependence on pulse number at different peak laser fluence values. Solid dots - experimental data points, solid line - fit by Equation (12). Pulse duration τ = 10 ps, laser wavelength λ = 1064 nm, repetition rate f_p = 100 kHz, peak laser fluences used F₀ = 18.4 J/cm² (w₀ = 21.2 µm), F₀ = 12.0 J/cm² (w₀ = 26.3 µm), and F₀ = 8.36 J/cm² (w₀ = 31.5 µm).