IFIMUP and IN-Instituto de Física dos Materiais da Universidade do Porto, Departamento de Física, Faculdade de Ciências, Universidade do Porto, R. do Campo Alegre 687,4169-007 Porto, Portugal.
Opt Lett. 2009 Dec 15;34(24):3851-3. doi: 10.1364/OL.34.003851.
We demonstrate the direct generation of sub-two-cycle pulses by soliton self-compression of femtosecond pulses from a Ti:sapphire laser at 85 MHz using a 4.85-mm-long highly nonlinear photonic crystal fiber. Sub-nanojoule, 41 fs input pulses were compressed down to 4.6 fs without additional phase compensation schemes. To our knowledge, these are the shortest pulses obtained by soliton-effect compression of a laser oscillator. Efficient, near-dispersionless collimation of the fiber output was achieved with a simple lens and an octave-spanning double-chirped mirror pair. The full electric field of the compressed pulses was retrieved with a genetic algorithm applied to spectral and interferometric autocorrelation measurements, and the results are well described by numerical simulations.
我们展示了通过使用 4.85 毫米长的高非线性光子晶体光纤对来自钛宝石激光器的飞秒脉冲进行孤子自压缩，直接产生亚两周期脉冲。41 飞秒、纳焦耳级的输入脉冲在没有额外相位补偿方案的情况下压缩到 4.6 飞秒。据我们所知，这些是通过激光振荡器的孤子效应压缩获得的最短脉冲。通过简单的透镜和一个覆盖一个倍频程的双啁啾镜对，可以实现光纤输出的高效、近无弥散准直。通过遗传算法应用于光谱和干涉自相关测量来恢复压缩脉冲的全电场，并通过数值模拟很好地描述了结果。
