An enhanced smoothing by spectral dispersion (SSD) scheme via the insertion of a complex coaxial vortex plate in the beamline is proposed. The complex coaxial vortex plate is comprised of an inner vortex plate that induces an azimuthal charge on the beam, and a surrounding vortex plate that induces an opposite charge on the beam. The surrounding vortex plate is supported by a base of same material that generates a time delay between the inner and the outer sub-beams. The time delay then brings about the frequency shift of the sub-beams with frequency modulation and spectral dispersion. As a result of the coherent superposition of the sub-beams, the focal spot exhibits a dominant envelope with transverse motion, and the inside speckles rotate rapidly in the picosecond regime. The simulation shows that the irradiation uniformity is slightly improved via the insertion of the complex coaxial vortex plate. More importantly, the laser-plasma interaction length is significantly shorten...

中文翻译：

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通过插入复杂的同轴涡旋板，通过频谱分散增强平滑度

通过在光束线中插入复杂的同轴涡旋板，提出了一种通过频谱色散（SSD）方案增强平滑的方法。复杂的同轴涡流板由一个内部涡流板和一个周围的涡流板组成，该内部涡流板在光束上感应出方位电荷，而周围的涡流板在光束上感应出相反的电荷。周围的涡流板由相同材料的底座支撑，该底座在内部和外部子光束之间产生时间延迟。然后，时间延迟导致子光束的频率偏移，并具有频率调制和频谱色散。由于子光束的相干叠加，焦点表现出具有横向运动的显性包络，并且内部的斑点在皮秒状态下快速旋转。仿真表明，通过插入复杂的同轴涡流板可以稍微提高辐照均匀度。更重要的是，激光-等离子体相互作用的长度大大缩短。