频域标定飞秒脉冲干涉自相关迹及钛宝石振荡器实时啁啾监测

Calibration of interferometric autocorrelation trace for femtosecond pulse in frequency domain and the real-time chirp diagnostic for Ti:sapphire oscillator

采用频域处理的方法首次在频域标定飞秒激光脉冲干涉自相关迹的时间扫描.计算被测脉冲的均方根宽度和啁啾参数,并以此为依据在实验中优化钛宝石振荡器的调节从而获得接近变换极限的11·5fs脉冲.该方法只涉及到数值积分和快速傅里叶变换,在实验中完全可以用于实时监测振荡器的运行情况.

The time delay of interferometric autocorrelation trace of femtosecond pulse was calibrated in frequency domain. By virtue of the calibrated interferometric autocorrelation trace, root-mean-square width and chirp parameter of the femtosecond pulse to be measured were calculated. Based on these parameters, the Ti: sapphire oscillator was optimized to generate 11.5 fs pulse in full width at half maximum, which was very close to the width of the transform-limited pulse. The measurement involved only an integration and a fast Fourier transform. Consequently, real-time chirp diagnostics for Ti: sapphire oscillator was feasible.