硅光电二极管激光损伤阈值随激光脉宽的变化

 对飞秒激光辐照下硅光电二极管损伤阈值进行了实验测量，对从1s到60fs不同脉宽激光辐照下硅光电二极管损伤阈值进行了讨论。实验数据表明，在1s到10ns脉宽范围内损伤所需能量密度近似而非严格地与脉宽的平方根成正比。信号分析表明硅光电二极管的损伤主要由热效应造成，而60fs激光辐照下的损伤阈值为0.1J/cm2，明显偏离普通温度分布预言的趋势。

Variation in damage thresholds of Si photodiodes with laser pulse duration

The damage thresholds of Si PIN photodiodes irradiated by 800nm fs laser with pulse duration of 60fs have been measured. The damage thresholds of Si photodiodes irradiated by laser pulse of different duration from 1s to 60fs are present and discussed. Experimental data indicates that damage fluence increases approximately but not strictly with square root of pulse duration for pulses longer than 10ns. The output signal analysis shows the damage was caused mainly by thermal effect. However the damage threshold to 60fs laser is 0.1J/cm~2, which deviates apparently from what general temperature distribution model predicted.