We demonstrate, for the first time, a single-shot, complete spatiotemporal measurement of pulses from a terawatt-scale, multi-stage-amplified, low repetition-rate laser source. The ultrashort pulse electric field, E(x,y,z,t), is spatiotemporally complex due to distortions that accrue from multiple chirped-pulse amplifiers, which requires a complete characterization. Meanwhile, the instability of the laser source introduces field profiles that vary significantly from pulse to pulse, which, together with the low repetition-rate (15 shots/hour), requires the use of a single-shot measurement technique. To accomplish the measurements, we used a wavelength-multiplexed, digital-holographic technique called Spatially and Temporally Resolved Intensity and Phase Evaluation Device: Full Information from a Single Hologram, specially tailored to measure picosecond pulses at a wavelength of about 1 μm. Specifically, individual pulses from the compact multipulse terawatt laser were measured, with up to 0.3 J per shot of energy and ∼2 ps pulse durations, at 1052 nm. With these measurements, we characterized several major spatiotemporal distortions that affect the peak intensity at the laser focus, as well as the pulse-shape instability on a shot-to-shot basis. Our technique allows detailed diagnosis of laser pulses (especially high-order spatiotemporal distortions) and provides straightforward four-dimensional animations of pulse propagation to a focus.

我们首次展示了对来自太瓦级、多级放大、低重复率激光源的脉冲进行单次、完整的时空测量。超短脉冲电场E ( x,y,z,t)，由于多个啁啾脉冲放大器产生失真，因此在时空上是复杂的，这需要完整的表征。同时，激光源的不稳定性引入了从脉冲到脉冲的显着变化的场分布，再加上低重复率（15 次/小时），需要使用单次测量技术。为了完成测量，我们使用了一种称为空间和时间分辨强度和相位评估装置：来自单个全息图的完整信息的波长多路复用数字全息技术，专门用于测量波长约为 1 μ 的皮秒脉冲米。具体而言，测量了来自紧凑型多脉冲太瓦激光器的单个脉冲，每次发射高达 0.3 J 的能量和约 2 ps 的脉冲持续时间，波长为 1052 nm。通过这些测量，我们表征了几个主要的时空失真，这些失真影响了激光焦点处的峰值强度，以及逐次发射的脉冲形状不稳定性。我们的技术允许对激光脉冲（尤其是高阶时空失真）进行详细诊断，并提供脉冲传播到焦点的直接四维动画。