摘要
基于能带理论,利用激光与光学材料相互作用的理论模型,研究了激光辐照下材料导带自由电子数密度的变化,讨论了材料损伤阈值与激光波长、脉冲宽度、材料禁带宽度之间的关系,数值分析了激光波长和脉冲宽度对损伤阈值的影响。结果表明:当脉宽小于1 ps时,材料损伤阈值随脉宽增大而减小;当脉宽大于1 ps时,材料损伤阈值随脉宽增大而增大;激光波长为10 fs^10 ns,损伤阈值随着波长的减小而减小。
A theory based on energy-band is used to study the free electron density in material conductive band and to investigate the interaction of laser and optical material. The relationship between the damage threshold and the laser-wave length, the pulse duration and the band gap is discussed. The influnces of laser wavelength and pulse duration on damage threshold are numerically analyzed. The conclusion shows that, when the pulse duration is shorter than 1 ps, the damage threshold decreases with the increas of pulse duration, while the pulse duration is longer than 1 ps, the damage threshold increases with the increasement of pulse duration, and laser-induced damage threshold in SiO2 decreases with the decreasement of laser wave length in range of 10 fs to 10 ns.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2008年第7期1071-1075,共5页
High Power Laser and Particle Beams
基金
国家自然科学基金项目(60508002)
关键词
材料损伤
损伤阈值
脉冲宽度
激光波长
Optical damage
Damage threshold
Pulse duration
Laser wavelength