激光脉宽对熔融石英中超连续光谱的影响

理论研究飞秒激光脉宽、啁啾和初始光谱对其在熔融石英中成丝产生的超连续光谱的影响.结果表明:在固定能量下,脉宽越大,蓝移截止波长越长,光谱强度越低.对脉宽大于150 fs的激光,负啁啾脉冲比无啁啾和正啁啾脉冲产生的蓝移光谱强度更大.

Influence of pulse duration on the supercontinuum generation from femtosecond laser filamentation in fused silica

The influences of the pulse duration, chirp， and initial spectrum of the femtosecond laser on the supercontinuum generated in fused silica have been investigated theoretically. Results show that, with the increase of the pulse duration, the cut-off wavelength of the blue-extension becomes longer and the spectral intensity becomes lower at the constant energy. For the laser with pulse duration larger than 150 fs, the spectral intensity of the blue-extension generated by the negatively chirped pulse is higher than those generated by the freely-chirped pulse and the positively chirped pulse.