高效、高峰值功率蓝光飞秒脉冲产生研究

分析计算了利用棱镜组引进频谱空间啁啾来补偿谐波倍频晶体的相位失配.结果表明，光谱 存在空间啁啾时，选择合适的透镜可在一定程度上补偿由于飞秒光脉冲的宽谱带引起的相位失配.采用此方法在实验上用自制的飞秒自锁模钛宝石激光器和BBO倍频晶体进行了二次谐波 倍频的研究，结果产生倍频蓝光的转换效率高达63%，蓝光平均输出功率达320mW，中心波长 为420nm，光谱带宽达5.5nm，可支持33.6fs的光脉冲.利用钛宝石激光器中的棱镜对进行波 长调谐，可使蓝光脉冲产生404—420nm的调谐范围.关键词：飞秒蓝光脉冲空间啁啾补偿二次谐波产生转换效率

GENERATION OF THE HIGH EFFICIENCY HIGH PEAK-POWER FEMTOSECOND BLUE OPTICAL PULSE

The analysis and calculation of the compensation for the phase mismatch of the f requency-doubling using the frequency space chirp introduced from prisms are mad e. The result shows that suitable lens can compensate the phase mismatch in a ce rtain extent resulting from wide femtosecond spectrum when the spectrum is space chirped. By means of this method, the experiment of second harmonic generatio n is carried out using a home-made femtosecond KLM Ti:sapphire laser and BBO cry stal. The conversion efficiency of SHG is 63%. The average output power of blue light is 320mW. The central wavelength is 420nm. The spectrum bandwidth is 5.5nm . It can sustain the pulse width of 33.6fs. The tuning range of blue light is 40 4-420nm，when the femtosecond Ti:sapphire optical pulse is tuned using the prism s in the cavity.