Czapla Nick, Nasir Derek M, Obst-Huebl Lieselotte, Zingale Anthony, Bin Jianhui, Gonsalves Anthony J, Steinke Sven, Nakamura Kei, Schroeder Carl B, Esarey Eric, Geddes Cameron G R, Schumacher Douglass W
SLAC National Accelerator Laboratory, Menlo Park, 94025, CA, USA.
Physics Department, The Ohio State University, Columbus, 43210, OH, USA.
Sci Rep. 2025 Jul 1;15(1):21115. doi: 10.1038/s41598-025-07016-3.
Exceptional pulse contrast can be critical for ultraintense laser experiments, particularly when using solid density targets, and their use is becoming widespread. However, current plasma mirror technology is becoming inadequate for the new generation of high repetition rate, high power lasers now available. We describe a novel double plasma mirror configuration based on renewable, free standing, ultrathin liquid crystal films tested at the BELLA Petawatt Laser Center. Although operating at a repetition rate of several shots per minute, this system can be scaled to a high repetition rate exceeding 1 Hz and represents an important step towards enabling sustained, continuous operation of plasma mirrors. We demonstrate an improvement of two to three orders of magnitude in contrast and a total throughput of 80%. We present the first measurements of a beam reflected from a single or double plasma mirror system using a wavefront sensor, showing a well preserved wavefront and spatial mode. Finally, we introduce a model that predicts the total throughput through this double plasma mirror. This is the first model that accurately predicts the peak reflectivity of a plasma mirror when given the laser temporal profile.
优异的脉冲对比度对于超强激光实验至关重要，特别是在使用固体密度靶时，并且其应用正在变得广泛。然而，当前的等离子体镜技术对于新一代现有的高重复频率、高功率激光器而言正变得不足。我们描述了一种基于可再生、独立、超薄液晶薄膜的新型双等离子体镜配置，该配置在BELLA拍瓦激光中心进行了测试。尽管该系统以每分钟几次的重复频率运行，但它可以扩展到超过1赫兹的高重复频率，并且代表了朝着实现等离子体镜的持续、连续运行迈出的重要一步。我们展示了对比度提高两到三个数量级以及80%的总通量。我们展示了使用波前传感器对从单等离子体镜或双等离子体镜系统反射的光束进行的首次测量，结果显示波前和空间模式得到了很好的保留。最后，我们引入了一个模型，该模型预测通过这种双等离子体镜的总通量。这是第一个在给定激光时间轮廓时能准确预测等离子体镜峰值反射率的模型。
