飞秒激光在水和玻璃中产生白光连续谱的试验研究

飞秒激光脉冲与透明介质相互作用后产生的白光具有类似激光束的高强度和高亮度特性,而且其谱线覆盖了从紫外到红外波段.分别利用10 Hz、120 fs、60 mJ的掺钛蓝宝石激光脉冲和1 kHz、120 fs、1 mJ的掺钛蓝宝石激光脉冲,在玻璃和水中产生了白光连续谱并进行了测量,测出了白光的谱线,实验结果显示白光谱宽分别为440～820 nm和400～750 nm;从自聚焦和自相位调制理论出发,对白光产生的机理进行了讨论,结果显示自聚焦和自相位调制无法完整的解释白光谱线.

Experimental Study on the White Light Continuum Induced by Interaction of Femtosecond Pulse with Water and Glass

The white light induced by interaction of femtosecond pulse with transparent materials has a property that is similar to laser beam,and has a continuous spectrum from ultraviolet to infrared.Two Ti：sapphire femtosecond laser systems with 10 Hz,120 fs,60 mJ and 1 kHz,120 fs,1 mJ were used to get the white continuum spectrum in the water and glass.The white continuum spectrum from 440 nm to 820 nm and 400nm to 750 nm are got.The generation of white light is discussed from the aspect of self-focusing and self-phase modulation.The experimental results show that the phenomenon of white continuum can＇t be explained by self-focusing and self-phase modulation theory alone.