During the laser application process, laser energy is usually converted into heat energy, causing high temperature, which affects the (high-speed) aircraft in routine flight. A completely novel photochemical method was investigated to potentially minimize the energy effect of the laser beam. Ag nanoparticles/C3N4 were synthesized by an ultra-low temperature reduced deposit method with Ag mean diameters of 5–25 nm for photofixation of N2. The absorption performance of laser can be improved by using appropriate charge density and small size Ag metal particles. The energy absorption rate was 7.1% over Ag/C3N4 (−40) at 5 mJ/cm2 of laser energy.

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In this paper, we propose a novel photonic crystal fiber (PCF) with double-layer rings for transmitting orbital angular momentum (OAM). The substrate of PCF is a pure silicon base. The inner circle is doped with Fluoride to reduce the refractive index (RI), and the transmission domain is doped with Germanium dioxide to increase the RI. On the outer side of the transmission ring, air holes are regularly arranged to restrict the beam transmission within the transmission layer. After calculation, the proposed OAM fiber can effectively support 118 OAM modes in the range of 1.3–1.75 μm with excellent characteristics. In addition, we also found that proposed fiber has “bandgap-like” mode field characteristics.