基于毫米级Au红外辐射抑制超材料的设计与制备  

Design and Fabrication of Millimeter-Scale Au Metamaterials with Infrared Radiation Suppression

作　　者：李晨曦 李享成[1] 陈平安[1] 朱颖丽 朱伯铨[1] Li Chenxi;Li Xiangcheng;Chen Ping'an;Zhu Yingli;Zhu Boquan(State Key Laboratory of Refractories and Metallurgy,Wuhan University of Science and Technology,Wuhan 430081,Hubei,China)

机构地区：[1]武汉科技大学省部共建耐火材料与冶金国家重点实验室,湖北武汉430081

出　　处：《光学学报》2024年第4期254-260,共7页Acta Optica Sinica

基　　金：国家自然科学基金(52304410,51972242);湖北省重大项目(2023BAA003);湖北省青年拔尖人才培养计划。

摘　　要：基于时域有限差分法仿真模拟了毫米级超材料的中远红外光谱响应,并结合电场散射效应分析了毫米方形图案的边缘电场分布对红外反射率的影响。通过参数扫描法优化得到了方形单元的最优厚度。将边缘区域离散化为独立单元,并将x、y方向分别设置为完美匹配层(PML)、periodic边界条件,通过迭代计算及加权叠加获得了毫米方形超材料的红外光谱响应及电场分布。结果表明,该超材料在2~16μm内的红外反射率保持在81.9%以上,最高可达87.05%。当图案占空比相同时,单元周期的减小增强了超材料边缘区域的电场散射效应,导致其在8~10μm远红外波段内的反射率保持在84.25%以上。实测结果与仿真结果较好地吻合,这为毫米级红外辐射抑制超材料的设计提供了新的思路。Objective Using infrared radiation suppression materials is regarded as an effective method to address the worsening thermal pollution owing to their favorable low-emission and radiation-cooling properties.According to the Stefan-Boltzmann law,the reduction of the thermal surface emissivity of a material can effectively suppress the infrared radiant energy.Metamaterial(MM)is an emerging branch of infrared radiation suppression materials with highly flexible spectral modulation capability and spectral designability.The infrared emission bandwidth and position will be precisely regulated by adjusting their pattern shapes and structure parameters,and thus the selective modulation of the infrared emission spectrum can be realized.However,due to the limitation of computer resources and computation power,it has always been challenging to directly obtain the infrared spectral response of millimeter-scale metamaterials through simulation software.Therefore,we hope to establish a computational model of the infrared spectral response of millimeter-scale metamaterials,which provides a novel approach for the design of broadband infrared radiation suppression functional devices.Methods In this paper,the mid-and far-infrared spectral response of millimeter-square metamaterials is simulated based on the time-domain finite-difference method.Combined with the electric field scattering effect,the impact of the marginal electric field strength distribution of the millimeter square pattern on the infrared reflectivity is analyzed.According to the traditional empirical formula,the computational model of the infrared spectral response of millimeter-square metamaterials is proposed.Using the full-wave electromagnetic simulation software FDTD and the parameter scanning method,the effects of the thicknesses of Au and SiO2 on the infrared spectral response are investigated,and the optimal thicknesses of the reflector layer and the substrate layer are identified.Herein,two square metamaterials with the same filling ratio and different unit

关 键 词：光学设计 毫米级超材料 电场散射效应 时域有限差分法 中远红外高反射 

分 类 号：TN213[电子电信—物理电子学]