Liao Zhongwei, Zhou Bingpu, Huang Yingzhou, Li Shunbo, Wang Shuxia, Wen Weijia
Appl Opt. 2014 Oct 1;53(28):6431-4. doi: 10.1364/AO.53.006431.
The Fano resonance induced by symmetry breaking could improve the sensitivity of localized surface plasmon resonance sensors. In this work, the spectra of gold nanocrescent arrays are measured and confirmed by simulation results through the finite element method (FEM). The Fano resonance presented in the spectra could be modulated by the symmetry breaking with different waist widths, which are understood through plasmonic hybridization theory with the help of surface charge distribution. Our results indicate the Fano lineshape is generated by the coherent coupling of the quadrupole plasmon mode Q of nanohole and the antibonding plasmon mode D(AB) of nanocrescent. Finally, the high figure of merit (FoM=1.6-3.5) of the Q mode in the visible region illustrates this nanocrescent Fano sensor is of great value in the biological and chemical scientific fields.
对称性破缺诱导的法诺共振可以提高局域表面等离子体共振传感器的灵敏度。在这项工作中，通过有限元方法（FEM）测量了金纳米新月阵列的光谱，并通过模拟结果进行了验证。光谱中呈现的法诺共振可以通过不同腰宽的对称性破缺来调制，借助表面电荷分布，通过等离子体杂交理论可以理解这一点。我们的结果表明，法诺线形是由纳米孔的四极等离子体模式Q和纳米新月的反键等离子体模式D(AB)的相干耦合产生的。最后，Q模式在可见光区域的高优值（FoM = 1.6 - 3.5）表明这种纳米新月法诺传感器在生物和化学科学领域具有重要价值。
