Improving the Energy Conversion Efficiency of a Laser-Driven Flyer by an In Situ-Fabricated Nano-absorption Layer.

Three kinds of Al flyer plates with different nanostructured absorption layers were in situ prepared by a direct laser writing technology to improve the energy conversion efficiency in a laser-driven flyer assembly. Microstructures, light absorption, and flyer velocity in the acceleration chamber were investigated. The reflectance for the flyers at 1064-nm wavelength can be reduced from 81.3 to 9.8% by the nanostructured absorption layer. The terminal velocity of a 50-μm-thick Al flyer irradiated by a 60-mJ laser pulse is 831 m/s, while the velocity of the flyer with an in situ-fabricated nano-absorption layer reaches up to 1113 m/s at the same condition. Resultantly, the energy conversion efficiency of the flyer with a nanostructure absorption layer can reach as high as 1.99 times that of the Al flyer. Therefore, the nanostructured absorption layer in situ prepared on the surface of a flyer provides a new method to significantly improve the energy conversion efficiency of a laser-driven flyer.