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Laser driven flyer (LDF) can drive small particles to ultrahigh speed (several km/s) by feeding pulse laser light, and exhibits giant application prospect in both of the civilian and military regions, such as the ignition of missile and spacecraft and dynamic high-pressure loading. In this work, we demonstrate a high-performance LDF by using the perfect metamaterial absorber (PMA) to improve the energy utilization efficiency of light. The designed Ag nanopillar array in anodic aluminum oxide templates (APA-AAO) were skillfully fabricated in-situ on the flyer layer surface, which can greatly reduce the reflectivity from 93% of the pure Al foil flyers to about 5% of the APA-AAO enhanced flyers. Our systematically transient analysis reveals that this ultralow reflectivity, together with the well-formed metal structure on Al foil, greatly improve both of the electron temperature and sustaining time of plasma formed in the ablating layer, and further enhances the acceleration process at both of the initial detonation wave generation stage (0–10 ns) and the following thermal expansion stage (10–200 ns). The final speed of the flyer generated in the PMA-enhanced LDF approach to 1730 m/s, which is about 1.4 times larger than that (1250 m/s) of the pure Al foil flyers. The transient electron temperature, transient flyer shadowgraph, plasma sustaining time, velocity, and accelerated velocity have been investigated systematically in this work. This PMA enhanced LDF provides an effective method for obtaining high-speed microparticles, and opens up a new perspective and guidance for designing high-performance LDF.

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.

The dramatic temperature rise of energetic materials when using only millisecond pulses of light is very important for photothermic ignition. Here we demonstrate a free-standing laser energy converter based on energetic graphene oxide, which exhibited an ultrafast and large temperature rise from 21 to 670 °C within 8.7 ms during the irradiation of laser pulses, while the temperature of the graphene-based laser energy converter can only be raised from 21 to 170 °C under the same conditions. The reason for the unexpected and much larger temperature rise of energetic graphene oxide than graphene was studied by laser scanning microscopy and thermal analysis, which indicated that the temperature rise is strongly dependent on the content of oxygen-containing groups in energetic graphene oxide. The combination process of focused ion beam and transmission electron microscope characterization was utilized for the direct observation of the layer-stacked structure in free-standing graphene oxide and graphene membranes. Furthermore, the initiating energy of laser initiators was 40% decreased by adding a thin layer of the free-standing laser energy converter based on energetic graphene oxide, which shows great potential for developing photothermic ignition with low initiating energy.

As a safe, reliable, and strongly electromagnetic resistant initiation method, laser initiation shows great promise in military blasting applications. Many obstacles exist when delivering a high-energy laser through optical fibers, directly influencing the energetic explosives under low-initiation conditions. Herein, we developed silver nanoplates as a laser energy absorber to reduce the laser initiation threshold and delay time. During the growth process of the silver seed nanoplates, mechanical disturbance was applied to provoke the nanoplates to develop more internal hotspots. Meanwhile, in ultraviolet visible near-infrared (UV–VIS-NIR) testing, the absorption peak was regulated to 808 nm by tailoring the size of the nanoplates. Results showed that the maximum temperature of the cracking nanoplates could reach 100 °C within 10 s, under the irradiation of an 808 nm diode laser at a power density of 1 W·cm−2. Through their use as a laser energy absorber, the silver nanoplates can effectively reduce the initiation threshold of cyclotrimethy lenetrinitramine (RDX) by 58.33% and reduce the delay time of B/KNO3 by 51.00%. This result provides potential applications for initiation energetic explosives at low laser energy.

Aluminum nanoparticles were added into cyclotrimethylenetrinitramine (RDX) to enhance the laser absorption and lower the initiation energy of pulse laser. Polyvinyl acetate (PVA), polyvinyl butyral (PVB), and fluororubber (F2314) were added into RDX as binders to prepare the RDX-based composite explosives with desirable mechanical behavior. The influence of aluminum nanoparticles and binders on the light absorption, thermal behavior, laser initiation energy and the electron temperature in aluminum plasma were investigated using reflectance spectroscopy, differential scanning calorimetry, laser initiation and laser-induced breakdown spectroscopy. Results showed that the addition of aluminum nanoparticles could prominently lower the laser initiation energy of the RDX-based explosives. The RDX doped with 2.0% aluminum nanoparticles could be reliably initiated with 1.5 J/cm2 laser energy (1064 nm, 8 ns). The laser initiation energy increased to 1.7, 2.4 and 2.9 J/cm2 with the additions of 0.5%, 1.0% and 2.0% F2314 binders, respectively. When the addition of PVA and PVB increased to 2.0%, the RDX-based explosives couldn’t be initiated by pulse laser. When the pulse laser radiated on the surface of the RDX-based composite explosives, the aluminum nanoparticles absorbed the laser energy and were heated to high temperature to initiate the explosives. The addition of binders can provide desirable mechanical behavior, but the laser initiation energy increased because the heat transmission from aluminum nanoparticles to RDX was hindered.