基于磁流变液的可控非线性电磁超材料关键技术研究

The microscopic electric/magnetic fields in electromagnetic metamaterials are much higher than the macroscopic fields carried by the propagation electromagnetic waves. It provides a potentional mechanism to enhance the nonlinear electromagnetic characteristics of materials and opens a new way to apply the electromagnetic metamaterials in nonlinear optics area. In this project, the key techniques of the controllable nonlinear electromagnetic metamaterials based on magnetorheological fluids are investigated in details, including the composing mechanisms, design methods, simulation methods, fabrication technics, and engineering application potentialities. By using the electrodynamics theory and elasticity theory, the composing and controlling mechanisms of the controllable nonlinear metamaterials based on magnetorheological fluids are investigated deeply. The theoretical frameworks of nonlinear effective media parameters and structures parameters of the electromagnetic metamaterials are analyzed by using both effective medium theory and transfer matrix approach. The nonlinear electromagnetic characteristics simulation methods of the electromagnetic metamaterial are established. The C/X-band controllable nonlinear electromagnetic metamaterial based on the magnetorheological fluids is designed and implemented, and its typical nonlinear properties generated from the interactions of the electric/magnetic resonators and propagating electromagnetic waves within the electromagnetic metamaterial are investigated experimentally, including the shifts of the electric/magnetic resonance frequencies depending on the power of incident electromagnetic waves, high-order harmonic generations, wave mixing, parametric amplifications and the ways to controll the nonlinear properties of the controllable nonlinear electromagnetic metamaterial. The approach to implement the controllable nonlinear optical mirrors, chiral metamaterials, electromagnetic absorbers and invisible cloaks using the controllable nonlinear electromagnetic metamaterials based on magnetorheological fluids are also studied in the project.The research results gained from this project are of great values in science and engineering, and have wide application potentialities in both military and civilian areas.

电磁超材料中微观电/磁场强度远高于入射电磁波的宏观场强度，据此可发展出增强材料的非线性电磁效应的新方法，将显著促进电磁超材料广泛应用于非线性光学技术领域。本项目旨在研究基于磁流变液的可控非线性电磁超材料的合成机理、设计方法、仿真技术、制造工艺、工程应用途径及方案。项目将综合应用电动力学及弹性理论，分析基于磁流变液的可控非线性电磁超材料的合成机理与控制机制；采用等效媒质理论及传输矩阵法，建立超材料的等效非线性电磁参数与材料结构参数的理论模型；研究超材料的非线性电磁特性仿真分析方法；设计研制C/X波段可控非线性电磁超材料，实验研究材料中微观电/磁谐振结构与电磁波互作用产生的频移、谐波、混频、参数放大等非线性特性及其控制途径；研究基于这类电磁超材料实现非线性光学镜、手征材料、吸波材料和隐身斗篷的技术方案。研究目标的实现在军事和民用领域有着迫切的应用需求，具有重要科学意义和工程应用价值。

本项目在国内外率先开展了基于磁流变液的可控非线性电磁超材料的合成机理、设计方法、仿真技术、制造工艺、工程应用途径及方案等关键技术研究，首次提出了面向电磁超材料应用的低损耗磁流变液基体制备技术，以及基于低损耗磁流变液的可控非线性电磁超材料的基本单元结构设计与仿真优化方法，研制出了C/X波段可控非线性电磁超材料样品，并对C/X波段材料样品进行了系统深入的实验测试研究验证，建立起了多物理场耦合理论分析体系、电磁仿真优化、材料制备工艺及样品测试等可控非线性电磁超材料系统研究方法。本项目在微波非线性电磁超材料的各参量之间相互耦合的机理及关系、各参量间非线性耦合动力学特性、非线性电磁超材料特性的受控机理及方法，在纳米尺度非线性电磁结构的多物理场耦合及模式转换、基于纳米尺度非线性电磁结构的低相噪射频/微波信号源和加速度计，在微波宽带可调谐吸波材料、手征材料、新型小型化微波无源器件、天线等方面均取得了系列重要理论成果和技术突破。本项目严格按照国家自然科学基金项目的研究目标，很好地完成了项目计划书要求的各项研究内容。本项目已发表学术成果75篇，其中SCI收录30篇（包括Applied Physics Letters、Optics Express、Scientific Reports等中科院JCR分区二区及以上论文5篇）、EI收录40篇、特邀报告3次，参编英文专著一章，论文受到Nature Communications等顶级期刊论文的引用和评价；申请发明专利8项，获得授权1项；获四川省科技进步奖三等奖1项、成都市科技进步奖三等奖1项，获中国电子教育学会优秀博士学位论文1篇。本项成功目培养了博士后1名、博士研究生6名、硕士研究生3名，其中两名博士毕业生还获得了2项自然科学基金（青年）项目，以及1项“全国博士后创新人才支持计划”项目。