The specific polarization of radially polarized lasers with cylindrical structures and longitudinal electric fields at their focal spots are of interest, as are the fundamental characteristics of electromagnetic (EM) solitons. Compared with linearly and circularly polarized lasers, radially polarized lasers have a more perfect symmetry, which makes them more suitable for studying the topological structure in laser–plasma interaction. We report the structural features of EM solitons induced via a radially polarized laser on the basis of three-dimensional particle-in-cell simulations. It has been discovered that a fractal-like structure is produced due to the interaction between the radially polarized laser and the plasma, and that this structure indirectly originates from the Weibel instability of the electron ring. This novel regime will allow potential applications such as the manipulation of relativistic electrons, mode filtering, and fractal-like particle acceleration.

具有圆柱形结构和在其焦点处的纵向电场的径向偏振激光器的特定偏振，以及电磁（EM）孤子的基本特性，都受到关注。与线性和圆偏振激光器相比，径向偏振激光器具有更完美的对称性，这使其更适合于研究激光-等离子体相互作用中的拓扑结构。我们在三维粒子模拟的基础上报告通过径向偏振激光诱导的电磁孤子的结构特征。已经发现由于径向偏振的激光与等离子体之间的相互作用而产生了分形结构，并且该结构间接地源自电子环的韦贝尔不稳定性。