A radially polarized beam is axially symmetric and is able to produce tightly focused light fields beyond the Gaussian beam diffraction limit. However, with the current technology, its duration is limited by the relatively narrow bandwidth that the generation techniques can support. Using a 10 cycle pulse with a central wavelength of 1.8 μm, we show that radially polarized beams can be compressed to the few-cycle regime, while still maintaining their radially polarized nature. Therefore, it seems feasible, using only well-developed methods, to reach focused intensities of $\sim {10}^{19}\mathrm{W}/{\mathrm{cm}}^2$. Conversion via high-harmonic generation will also open a route for applications in attosecond science, especially for a wide range of optical measurements and optical control that require high spatial and high temporal resolution.

中文翻译：

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产生几个周期的径向极化脉冲

径向偏振光束是轴向对称的，并且能够产生超出高斯光束衍射极限的紧密聚焦的光场。但是，对于当前技术，其持续时间受到生成技术可以支持的相对较窄的带宽的限制。使用中心波长为1.8μm的10个周期的脉冲，我们显示了径向偏振光束可以压缩到几个周期的状态，同时仍保持其径向偏振特性。因此，仅使用发达的方法来达到集中的强度似乎是可行的。$〜{10}^{19}\mathrm{w\; ^}/{\mathrm{厘米}}^{\mathrm{2个}}$。通过高谐波产生的转换也将为在阿秒科学中的应用开辟一条道路，尤其是对于要求高空间和高时间分辨率的各种光学测量和光学控制。