UV laser pulses at 266 nm with 170 ps duration and up to 300 mJ energy create UV filaments. The effects of different beam preparation scenarios on UV filamentation are discussed. Beam preparation by focusing in vacuum and launching into the atmosphere through an aerodynamic window establishes the existence of filaments as self-guided non-diffracting entities. In addition, focusing through the aerodynamic window converts the initial super-Gaussian into a parabolic beam profile at the edge of the nonlinear medium (air). The shock-wave generated by the UV filament is investigated via shadowgraphy techniques. The shock-wave is cylindrically symmetric, leaving a low density channel behind, which is well-sustained for 1 ms, as it propagates outward. This low density channel is a waveguide that can be used for guiding purposes. Applications of UV filaments including guiding, remote sensing, and drag reduction for supersonic aircrafts are discussed.

中文翻译：

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UV灯丝及其应用的研究

具有 170 ps 持续时间和高达 300 mJ 能量的 266 nm 紫外激光脉冲可产生紫外灯丝。讨论了不同光束制备方案对 UV 成丝的影响。通过在真空中聚焦并通过空气动力学窗口发射到大气中的光束准备建立了作为自导非衍射实体的细丝的存在。此外，通过空气动力学窗口聚焦将初始超高斯转换为非线性介质（空气）边缘的抛物线光束轮廓。紫外灯丝产生​​的冲击波通过阴影描记技术进行研究。冲击波是圆柱对称的，留下一个低密度通道，当它向外传播时，它可以很好地维持 1 毫秒。这个低密度通道是一个波导，可用于引导目的。