Li Fujian, Ji Lailin, Zhao Xiaohui, Xia Lan, Liu Dong, Shi Haitao, Feng Wei, Rao Daxing, Cui Yong, He Ruijing, Xie Qingnan, Li Xiaoli, Ma Weixin, Sui Zhan, Gao Yanqi
Opt Express. 2022 Jun 6;30(12):21906-21917. doi: 10.1364/OE.458705.
We propose a random polarization smoothing method for low-coherence laser to obtain focal spot with random polarization that evolves rapidly in sub-picosecond timescales. Random polarization smoothing is realized by a half-aperture wave plate with sufficient thickness. The degree of polarization and polarization evolution of the focal spot are studied theoretically. The calculation results show that random polarization smoothing can make the polarization of focal spot evolve rapidly and randomly in time and space. Experimentally, the polarization of the focal spot of low-coherence laser with random polarization smoothing is measured by a single-shot polarimeter. The measurement results show that the degree of polarization of the focal spot is reduced to 0.22 on average, which proves the effectiveness of random polarization smoothing. The random polarization smoothing technique on low-coherence laser is expected to reduce the laser plasmas instability through its multi-dimensional random evolution properties.
我们提出了一种用于低相干激光的随机偏振平滑方法，以获得具有随机偏振的焦斑，该焦斑在亚皮秒时间尺度上快速演化。随机偏振平滑通过具有足够厚度的半孔径波片实现。从理论上研究了焦斑的偏振度和偏振演化。计算结果表明，随机偏振平滑可使焦斑的偏振在时间和空间上快速且随机地演化。实验上，利用单次偏振计测量了具有随机偏振平滑的低相干激光焦斑的偏振。测量结果表明，焦斑的偏振度平均降低到0.22，这证明了随机偏振平滑的有效性。低相干激光的随机偏振平滑技术有望通过其多维随机演化特性降低激光等离子体不稳定性。
