Ablation of insulators under the action of short pulses of X-ray plasma lasers and free-electron lasers

作者：Inogamov N A^*; Anisimov S I; Petrov Yu V; Khokhlov V A; Zhakhovski V V; Faenov A Ya; Pikuz T A; Fortov V E; Skobelev I Yu; Kato Y; Shepelev V V; Fukuda Y; Tanaka M; Ishino M; Nishikino M; Kando M; Kawachi T; Kishimoto M; Nagasono M; Tano K; Ishikawa T; Ohashi N; Yabashi M; Togashi T; Senda Y

来源：Journal of Optical Technology, 2011, 78(8): 473-480.

An experimental and theoretical study has been carried out of the ablation of a solid insulator with a wide band gap (LiF) under the action of ultrashort laser pulses of the UV range, obtained in a free-electron laser (pulse width tau(L) = 0.3 ps, photon energy (h) over bar omega(L) = 20.2eV), and the soft X-ray region, obtained in a silver-plasma laser (tau(L) = 7 ps, (h) over bar omega(L) = 89.3 eV). A comparison is made of the results obtained on the two laser systems. It is shown that the ablation threshold is about the same for both lasers. A theory is presented that explains the weak growth of the ablation mass with increasing surface energy density of the laser radiation (the fluence) in the case of X-ray lasers as a result of the transition from spallation close to the ablation threshold to evaporative ablation at high fluence values.

• 出版日期2011-8