▎ 摘 要
The nonlinear transmission of multilayer (similar to 12 layers) graphene at the wavelength lambda similar to 10 mu m is measured for the first time. The absorption saturation intensity in graphene (similar to 330 kW cm(-2)) and the ablation threshold of its outer layers (similar to 1 MW cm(-2), 0.11 J cm(-2)) under action of a CO2 laser pulse with a duration of 70-85 ns at lambda = 10.55 mu m are determined. The residual absorption of graphene at its partial saturation was 48 % of the initial value. This is significantly smaller than the value measured previously for samples with a close number of layers at lambda = 1.55 mu m (92.3 %-93.8 %). It is shown that the ablation threshold of two graphene layers adjacent to the BaF2 substrate (after successive ablation of outer layers) exceeds 0.27 J cm(-2).