150 fs~10 ps脉宽下熔石英激光损伤的仿真与分析

基于约化电子数密度增长速率方程，建立了熔石英导带电子数密度随脉冲持续时间变化的模型。利用电子数临界密度这一概念，得到了150 fs~10 ps脉宽下，熔石英激光损伤阈值范围。分析表明，5~10 ps，雪崩电离仍然起主要作用，而光致电离提供的初始电子使雪崩电离不再依赖材料原有的初始电子; 当脉宽减小到约为4 ps时，光致电离与雪崩电离作用相等; 之后，光致电离起主要作用。通过仿真出的损伤阈值拟合，得到了该脉宽区间下新的脉宽定律: 熔石英的损伤阈值正比于脉宽的0.38次方; 考虑温度对熔石英损伤阈值的影响，熔石英的损伤阈值正比于脉宽的0.34次方。

Abstract

Based on the reduced growth rate equation of electron density, a theoretical model is established to describe the change of the conduction band electron density of fused silica with the laser pulse duration. Using the concept of the critical electron density, a scope of the laser-induced damage of fused silica is calculated with the pulse width from 150 fs to 10 ps. The analysis shows that the avalanche ionization still takes a leading role from 5 ps to 10 ps. Instead of electrons provided by the fused silica itself, the initial electrons produced by the photoionization make a contribution to the impact ionization. It reaches a balance between avalanche ionization and photoionization when the pulse width shrinks to 4 ps. After that, the photoionization plays a main role in the growth of the conduction band electron density. Through the fitting curve, a new pulse width law is obtained to satisfy the laser-induced damage threshold changing from 150 fs to 10 ps. The results demonstrate that the threshold is proportional to tp0.38(tp is the pulse width), and changes to tp0.34 when the temperature dependence is concerned.

参考文献

[1] Bennett H E, Glass A J, Guenther A H, et al. Laser induced damage in optical materials: twelfth ASTM symposium[J]. Applied Optics, 1981, 20(17): 3003-3019.

[2] Manenkov A A. Fundamental mechanisms of laser-induced damage in optical materials: understanding after 40 years of research[C]//Florida: International Society for Optics and Photonics. 2008: 713202.

[3] Bloembergen N. Laser-induced electric breakdown in solids[J]. Quantum Electronics, 1974, 10(3): 375-386.

[4] Koldunov M F, Manenkov A A, Pokotilo I L. Laser-induced damage criterion[C]//Florida: International Society for Optics and Photonics, 1997: 506-525.

[5] Koldunov M F, Manenkov A A. Recent progress in theoretical studies of laser-induced damage (LID) in optical materials: fundamental properties of LID threshold in the wide-pulse-width range from microseconds to femtoseconds[C]//Florida: International Society for Optics and Photonics, 1999: 212-225.

[6] Rajeev P P, Gertsvolf M, Corkum P B, et al. Field dependent avalanche ionization rates in dielectrics[J]. Physical Review Letters, 2009, 102: 083001.

[7] Manenkov A A. Fundamental mechanisms of laser-induced damage in optical materials: today’s state of understanding and problems[J]. Optical Engineering, 2014, 53: 010901.

[8] Gruzdev V. Fundamental mechanisms of laser damage of dielectric crystals by ultrashort pulse: ionization dynamics for the Keldysh model[J]. Optical Engineering, 2014, 53: 122515.

[9] 翟玲玲, 冯国英, 高翔, 等. 杂质诱导熔石英激光的损伤机理[J]. 强激光与粒子束, 2013, 25(11): 2836-2840. (Zhai Lingling, Feng Guoying, Gao Xiang, et al.Mechanism of laser damage induced by inclusions in fused silica.High Power Laser and Particle Beams, 2013, 25(11): 2836-2840)

[10] Du D, Liu X, Korn G, et al. Laser-induced breakdown by impact ionization in SiO2 with pulse widths from 7 ns to 150 fs[J]. Applied Physics Letters, 1994, 64(23): 3071-3073.

[11] Stuart B C, Feit M D, Rubenchik A M, et al. Laser-induced damage in dielectrics with nanosecond to subpicosecond pulses[J]. Physical Review Letters, 1995, 74(12): 2248-2251.

[12] Varel H, Ashkenasi D, Rosenfeld A, et al. Laser-induced damage in SiO2 and CaF2 with picosecond and femtosecond laser pulses[J]. Applied Physics A, 1996, 62(3): 293-294.

[13] Sheehan L M, Hendrix J L, Battersby C L, et al. National ignition facility small optics laser-induced damage and photometry measurements program[C]//Florida: International Society for Optics and Photonics, 1999: 518-524.

[14] Koldunov M F, Manenkov A A, Pokotilo I L. Pulse-width and pulse-shape dependencies of laser-induced damage threshold to transparent optical materials[C]//Florida: International Society for Optics and Photonics, 1996: 718-730.

[15] Gulley J R, Winkler S W, Dennis W M. Simulation and analysis of ultrafast-laser-pulse-induced plasma generation in fused silica[J]. Optical Engineering, 2008, 47: 054302.

[16] Gulley J R. Ultrafast laser-induced damage and the influence of spectral effects[J]. Optical Engineering, 2012, 51: 121805.

[17] 陈发良, 李东海. 基于 Fokker-Planck 方程的电介质材料短脉冲激光破坏机制分析[J]. 强激光与粒子束, 2011, 23(2): 334-338.(Chen Faliang, Li Donghai. Mechanisms of short-pulse laser induced damage in dielectric based on Fokker-Planck equation. High Power Laser and Particle Beams, 2011, 23(2): 334-338)

[18] 罗晋, 刘志超, 陈松林, 等. 多脉冲激光辐照下介质损伤理论研究[J]. 强激光与粒子束, 2013, 25(12): 3301-3306.(Luo Jin, Liu Zhichao, Chen Songlin, et al. Theoretical research of multi-pulses laser induced damage in dielectrics. High Power Laser and Particle Beams, 2013, 25(12): 3301-3306)

[19] Wu A Q, Chowdhury I H, Xu X. Femtosecond laser absorption in fused silica: Numerical and experimental investigation[J]. Physical Review B, 2005, 72: 085128.

[20] Mikami K, Motokoshi S, Fujita M, et al. Laser-induced damage thresholds in silica glasses at different temperature[C]//Florida: International Society for Optics and Photonics, 2009: 75041R.

[21] Mikami K, Motokoshi S, Somekawa T, et al. Temperature dependence of laser-induced damage thresholds by short pulse laser[C]// Florida: International Society for Optics and Photonics, 2012: 853005.

王金舵, 郭喜庆, 余锦. 150 fs~10 ps脉宽下熔石英激光损伤的仿真与分析[J]. 强激光与粒子束, 2015, 27(4): 041002. Wang Jinduo, Guo Xiqing, Yu Jin. Simulation and analysis of laser-induced damage in fused silica with pulse widths from 150 fs to 10 ps[J]. High Power Laser and Particle Beams, 2015, 27(4): 041002.

150 fs~10 ps脉宽下熔石英激光损伤的仿真与分析

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