Radially polarized laser beams, which could generate longitudinal electric fields (LEF) in the far field after being focused have drawn increasing interest in wide fields. However, it is difficult to boost a radially polarized laser pulse to high peak power due to its spatially inhomogeneous polarization distribution. Here, we propose a vector superposition approach, firstly partition a linearly polarized beam into two parts in the near field, secondly modulate their polarization direction separately using the electro-optical effect and finally focus them using a high numerical aperture lens, thereby generating the LEF in the far field owing to vector superposition. This approach can amplify a laser pulse to the required peak power by using traditional schemes of the linearly polarized seed-pulse generation and multi-pass amplification, thereby efficiently scaling the LEF to the required magnitude. The simulation results support the theory in concluding that the approach would be a competent way to achieve super strong LEF in the far field of a laser beam.

径向偏振激光束在聚焦后可以在远场产生纵向电场（LEF），这在宽场中引起了越来越多的兴趣。然而，由于其空间不均匀的偏振分布，很难将径向偏振激光脉冲提升到高峰值功率。在这里，我们提出了一种矢量叠加的方法，首先在近场将线偏振光束分成两部分，然后利用电光效应分别调制它们的偏振方向，最后利用高数值孔径透镜将它们聚焦，从而产生 LEF在远场由于矢量叠加。这种方法可以通过使用线性偏振种子脉冲生成和多通道放大的传统方案将激光脉冲放大到所需的峰值功率，从而有效地将 LEF 缩放到所需的幅度。仿真结果支持该理论，即该方法将是在激光束远场中实现超强 LEF 的有效方法。