Diop Saaxewer, Bonod Nicolas, Chorel Marine, Lavastre Éric, Roquin Nadja, Heymans Lilian, Brianceau Pierre, Gallais Laurent, Lamaignère Laurent
Opt Lett. 2023 Sep 1;48(17):4669-4672. doi: 10.1364/OL.498295.
The peak-power of petawatt-class lasers is limited by laser-induced damage to final optical components, especially on the pulse compression gratings. Multilayer dielectric (MLD) gratings are widely used in compressor systems because they exhibit a high diffraction efficiency and high damage threshold. It is now well established that the etching profile plays a key role in the electric field distribution, which influences the laser damage resistance of MLD gratings. However, less attention has been devoted to the influence of the multilayer design on the laser damage resistance of MLD gratings. In this Letter, we numerically and experimentally evidence the impact of the dielectric stack design on the electric field intensity (EFI) and the laser-induced damage threshold (LIDT). Three different MLD gratings are designed and manufactured to perform laser damage tests. On the basis of the expected EFIs and diffraction efficiencies, the measured LIDTs show how the multilayer design influences the laser resistance of the MLD gratings. This result highlights the impact of the multilayer dielectric design on the electric field distribution and shows how to further improve the laser-induced damage threshold of pulse compression gratings.
拍瓦级激光器的峰值功率受到最终光学元件激光诱导损伤的限制，尤其是脉冲压缩光栅。多层介质（MLD）光栅因其具有高衍射效率和高损伤阈值，而被广泛应用于压缩器系统。目前已经明确，蚀刻轮廓在电场分布中起着关键作用，这会影响MLD光栅的抗激光损伤能力。然而，多层设计对MLD光栅抗激光损伤能力的影响却较少受到关注。在本信函中，我们通过数值模拟和实验证明了介质堆叠设计对电场强度（EFI）和激光诱导损伤阈值（LIDT）的影响。设计并制造了三种不同的MLD光栅以进行激光损伤测试。基于预期的电场强度和衍射效率，测量得到的激光诱导损伤阈值展示了多层设计如何影响MLD光栅的抗激光能力。这一结果突出了多层介质设计对电场分布的影响，并展示了如何进一步提高脉冲压缩光栅的激光诱导损伤阈值。
