摘要
提出了一种由圆柱纳米孔阵列组成的全介质超表面折射率传感器,通过平移纳米孔引入结构单元的面内对称性破坏,非对称的介质纳米孔阵列可以实现由电四极子(EQ)激发的具有高品质因数(Q值)的准连续域束缚态(BIC)共振模式。从理论上分析了结构非对称参数与Fano共振的辐射Q值之间的关系,证明了该模式为对称保护BIC模式,并进行近场分析和多极分解,证明了EQ在共振模式中占主导作用,同时分析了结构参数对Fano共振的影响,并计算了介质折射率的光谱响应,得到结构的灵敏度可达512 nm/RIU(折射率单元)、Q值为2568.7、优质因数(FOM)为760,所提结构在近红外范围内的高灵敏生物传感器领域具有潜在的应用价值。
In this study,an all-dielectric metasurface refractive-index sensor consisting of an array of cylindrical nanoholes is proposed.In-plane symmetry breaking of the structural unit is introduced by translating the nanoholes,and asymmetric dielectric nanohole arrays can achieve quasi-bound states in the continuum(BIC)resonance mode with a high-quality factor(Q-factor)by electric quadrupole(EQ).The relationship between the structural asymmetry parameters and the radiative Qfactor of the Fano resonance is theoretically analyzed.It is found that the mode is a symmetry-protected BIC,and nearfield analysis and multipole decomposition show that the EQ plays a dominant role in the resonance mode.In addition,the influence of structural parameters on Fano resonance is analyzed,and the spectral response of the refractive index of the medium is calculated.The sensitivity of the structure reaches up to 512 nm/RIU(refractive index unit),the Q-value is 2568.7,and the figure of merit(FOM)is 760.The proposed structure has potential applications in highly sensitive biosensors in the near-infrared range.
作者
赵静
王加贤
高丽贞
邱伟彬
Zhao Jing;Wang Jiaxian*;Gao Lizhen;Qiu Weibin(Computer Science and Information Engineering School,Xiamen Institute of Technology,Xiamen 361021,Fujian,China;College of Information Science and Engineering,Huaqiao University,Xiamen 361021,Fujian,China)
出处
《激光与光电子学进展》
CSCD
北大核心
2023年第19期230-235,共6页
Laser & Optoelectronics Progress
基金
福建省中青年教师教育科研项目(JAT210562)
厦门工学院嵌入式人工智能计算及应用科研创新团队(KYTD202003)
计算机科学与信息工程学院院级科研基金(EEKY202101)。
关键词
全介质超表面
Fano共振
连续域束缚态
折射率传感
all-dielectric metasurface
Fano resonance
bound state in the continuum
refractive index sensing
