基于Fano共振的全介质超表面双参数传感器  

All⁃Dielectric Metasurface Dual⁃Parameter Sensor Based on Fano Resonance

作　　者：南雪莹 刘会刚[1,2] 刘海涛 Nan Xueying;Liu Huigang;Liu Haitao(Engineering Research Center of Thin Film Optoelectronics Technology,Ministry of Education,College of Electronic Information and Optical Engineering,Nankai University,Tianjin 300350,China;Department of Microelectronic Engineering,College of Electronic Information and Optical Engineering,Nankai University,Tianjin 300350,China;Institute of Modern Optics,College of Electronic Information and Optical Engineering,Nankai University,Tianjin 300350,China;Tianjin Key Laboratory of Micro-scale Optical Information Science and Technology,Tianjin 300350,China)

机构地区：[1]南开大学电子信息与光学工程学院薄膜光电子技术教育部工程研究中心,天津300350 [2]南开大学电子信息与光学工程学院微电子工程系,天津300350 [3]南开大学电子信息与光学工程学院现代光学研究所,天津300350 [4]天津市微尺度光学信息技术科学重点实验室,天津300350

出　　处：《中国激光》2024年第2期162-170,共9页Chinese Journal of Lasers

基　　金：国家自然科学基金(62075104)。

摘　　要：与金属超表面相比,全介质超表面具有较低的欧姆损耗和较尖锐的共振峰。提出了一种基于“θ”形全介质硅超表面的双参数传感器。通过增加空孔破坏周期单元结构的对称性,从而产生两个Fano共振峰,其中第一个Fano共振峰为连续域中的准束缚态(QBIC),两个峰的光谱对比度分别为71.4%和99.4%。利用商用多物理场仿真软件COMSOL对该超表面周期结构进行模拟仿真,结果表明,传感器在两个Fano共振峰处的折射率传感灵敏度分别为278.9 nm·RIU-1和230.0 nm·RIU^(-1),优值(FOM)最大为9387,品质因子(Q)最大为9735。本传感器能够同时实现折射率和温度的双参数测量,仿真结果显示两个共振峰的温度传感灵敏度分别为18.86 pm·℃^(-1)和42.71 pm·℃^(-1)。Objective Currently,the performance of refractive-index sensors based on metal metasurfaces is limited by their low quality factors,due to significant Ohmic losses in the metal material.Sensors based on all-dielectric metasurfaces can overcome these disadvantages.However,most dielectric refractive-index sensors neglect the impact of temperature fluctuations.Hence,they experience crosstalk between the refractive index and environmental temperature.In this study,we design a dual-parameter sensor based on the“θ”shaped all-dielectric silicon metasurface.Two Fano resonance peaks are generated by adding an empty hole to break the symmetry of the periodic units in the structure.The sensor can simultaneously measure both the refractive index and temperature by measuring the wavelengths of the two Fano resonances.Methods In this study,we use the commercial multiphysics simulation software COMSOL to numerically solve Maxwell equations for an all-dielectric dual-parameter metasurface sensor.We set periodic boundary conditions along the x-and y-directions and place two ports above and below the metasurface structure in the z-direction.An incident plane wave,polarized along the x-axis,is set at the upper port.The zeroth-order plane-wave transmittance is calculated at the lower port.To prevent undesirable reflections,perfectly matched layers(PMLs)are introduced outside each port.The maximum finite-element mesh size is set to 1/10 of the minimum incident wavelength.The scanned wavelength range is 1000‒1200 nm.The relationship between the Fano resonance and quasi-bound state in the continuum(QBIC)is analyzed by varying the structural asymmetry parameter of the metasurface and calculating the corresponding quality factors.Results and Discussions The designed structure exhibits high values of sensitivity,quality factor(Q),and figure of merit(FOM).Two Fano resonances can be generated by breaking the symmetry of the periodic unit structure.The first Fano resonance peak is a QBIC with an ultrahigh Q in the near-infrared band(F

关 键 词：传感器 Fano共振 全介质超表面 折射率传感 温度传感 

分 类 号：O436[机械工程—光学工程]