Abstract We analyze, via an off-axis incident model and three-dimensional particle-in-cell simulations, the influence of beam pointing fluctuations (BPFs) on the propagation properties of relativistic laser pulses in micro-tubes. It is observed that the in-tube laser intensity can be further amplified in the BPFs-induced off-axis incident case. But the intensification factor exhibits strong polarization-dependence. When the laser pulse is linearly polarized in the off-axis incident plane (p-polarization), more electrons may be dragged out from about a half of the tube inner surface in each across section than in the on-axis incident case, enhancing the effects of relativistic nonlinearity and channel focusing. The area for generating more electrons is reduced by one half in the s-polarization case, resulting in less efficient light intensification. The BPFs-induced off-axis incident also leads to pulse shortening. Moreover, light confinement in the tube core is evident and the laser pulse tends to be coaxial with the tube.

中文翻译：

---

相对论激光脉冲的增强和定位对抗微管等离子体透镜的指向波动

摘要 我们通过离轴入射模型和三维细胞内粒子模拟分析了光束指向脉动（BPF）对微管中相对论激光脉冲传播特性的影响。观察到，在 BPF 引起的离轴入射情况下，管内激光强度可以进一步放大。但是增强因子表现出很强的极化依赖性。当激光脉冲在离轴入射平面（p 极化）中线性极化时，与在轴入射情况下相比，每个横截面中大约一半的管内表面可能会拖出更多的电子，从而增强相对论非线性和通道聚焦的影响。在 s 偏振情况下，产生更多电子的面积减少了一半，导致光增强效率较低。BPF 引起的离轴事件也会导致脉冲缩短。此外，管芯中的光限制很明显，激光脉冲往往与管同轴。