基于飞秒激光加工技术的微波和可见光双频段隐身器件机理研究

The invisibility techniques developed rapidly recent decades due to their utmost importance in the present unbalanced wars. However, the present military invisibility equipment can only work in one frequency band for one specific type of detector. Kinds of invisibility devices against different detectors would waste a lot of areas and load on the weapon. To solve this critical problem, the dual-band integrated invisibility cloaks at microwave and optical frequency simultaneously is going to be achieved. In the project, we will firstly propose the forward-backward mixed design recipe for dual-band invisibility cloaks; then improve the fabrication techniques for optically transparent metallic nanostructure on the anisotropic optical substrate materials; and demonstrate dual-band invisibility cloaks experimentally. A 90% reduction of the total scattering cross section with 5% relative bandwidth is to be achieved at microwave regime, while optical ray path recovery will be achieved at the wavelengths from 450 to 650nm with 85% transparency simultaneously, with only one metamaterial-based cloak. Our work might pave the way for multi－frequency compact and integrated invisibility cloak for the next-generation military invisibility equipment.

隐身技术在当代战争中占据着极其重要的地位。然而，目前没有任何一种隐身技术能够同时在微波和可见光这两个频段实现全方向隐身。为了应对复杂的战场环境，兵器需要同时装备多种不同频段的隐身器件，这会造成隐身器件之间的彼此干扰，浪费兵器有限的空间和载荷。为了解决这一问题，本项目拟通过建立双频段超构材料参数的调控机理模型，提出双频段隐身器件的前向-逆向混合设计方法，实现微波和可见光双频段隐身器件。申请人拟利用飞秒激光加工技术，在各向异性光学透明材料上制备透明金属微结构阵列，并用此超构材料搭建隐身器件。该双频段隐身器件将在15GHz附近达到相对带宽5%、总散射横截面积降低90%的技术指标；同时，在450nm-650nm的可见光频段实现光路复原、整体透光率大于85％的光学隐身性能。本项目的研究将为多频段隐身器件的设计提供潜在的解决思路，为我国隐身装备的技术发展做出贡献。

本项目围绕微波和可见光这两个在隐身领域极为重要的波段，研究了超构材料当中人工微结构等效电磁特效的跨尺度调控方法，建立了组合波段隐身技术集成方法，利用激光刻蚀、纳米压印、物理气相沉积等工艺，实现了多种功能复合的电磁隐身器件，并进行了相关的测试和物理学原理验证，包括与能源系统集成的卫星隐身技术、三维各向同性光子晶体的多功能色散调控、全介质超构材料簇内/簇间作用下的电磁辐射调控等一系列相关工作。本项目的研究将为多频段隐身器件的设计提供潜在的解决思路，为我国隐身装备的技术发展做出贡献。