摘要
针对脉冲宽度约1 ns、波长为351 nm的三倍频紫外激光,定量分析了熔石英介质中的自聚焦长度、峰值光强与强紫外激光光束质量及环境条件等因素的关系,研究了产生紫外光非线性自聚焦效应的阈值条件。研究结果表明:在强紫外激光光束质量一定的前提下,可将B积分值定义为自聚焦的阈值条件;入射强紫外激光光束质量越差,在熔石英介质中产生自聚焦的阈值条件越低;即使对于空间分布均匀的理想光束,当空气中存在灰尘时,经过一段距离的传输后,在熔石英介质中将导致强紫外激光自聚焦效应的产生,且灰尘尺寸较大时的自聚焦效应较明显,自聚焦的阈值条件也相对较低。
The effects of the environmental condition and the beam quality of the third harmonic UV laser with a pulse width of about 1 ns and a wavelength of 351 nm on the self-focusing intensity and self-focusing distance in fused silica were analyzed. The threshold of the nonlinear self-focusing of the UV laser was studied. The results show that, for the given beam quality of UV laser, the value of B integral remains almost the same, which can be defined as the threshold of the nonlinear self-focusing effect. The worse the beam quality is, the lower the threshold is. Furthermore, the dusts in the air can induce self-focusing in fused silica even for the input UV laser with uniform intensity and phase distributions. Moreover, when the dust particle is larger, the self- focusing effect is more obvious and the threshold is lower.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2006年第10期1653-1656,共4页
High Power Laser and Particle Beams
基金
四川省青年科技基金资助课题(05ZQ026-013)
