论文部分内容阅读
基于椭球模型,考虑到脉冲激光的能量传播特性,提出了聚焦区域的光强的表达式,分析了液体中光击穿的机制,对于多光子电离诱导的雪崩电离,简化了等离子体中自由电子密度演化过程的速率方程,修正了电子扩散速率和雪崩电离速率,得到了雪崩电离产生的自由电子密度的解析表达式,并利用雪崩电离产生的自由电子密度的解析表达式,得到了长、短脉宽的雪崩电离击穿光强阈值的解析表达式,进而讨论了长、短脉宽激光情况下,脉冲宽度、初始电子密度、扩散速率以及复合速率对击穿阈值的影响。此外,通过该解析表达式得到的光强阈值与实验结果符合较好。
Based on the ellipsoid model and taking into account the energy propagation characteristics of the pulsed laser, the expression of the light intensity in the focused region is proposed. The mechanism of light breakdown in the liquid is analyzed. The avalanche ionization induced by multiphoton ionization is simplified and the plasma free The electron density diffusion rate and the avalanche ionization rate are corrected. The analytical expressions of the free electron density generated by the avalanche ionization are obtained, and the analytical expressions of the free electron density generated by the avalanche ionization are obtained. Short pulse width of the avalanche ionization breakdown threshold value of the analytical expression, and then discussed the case of long, short pulse width laser pulse width, initial electron density, diffusion rate and composite rate of the breakdown threshold. In addition, the light intensity threshold obtained by the analytical expression is in good agreement with the experimental results.