A plasmonic nanostructure composed of a displaced elliptical disk in a nonconcentric split ring is proposed and investigated theoretically by the finite difference time domain method. The simulated scattering spectra and electric field distributions reveal that multiple Fano resonances can be formed due to the destructive interference of the longitudinal dipole mode of the disk and multiple multipole magnetic modes of the split ring. It is also found that the spectral position of each Fano dip is insensitive to the offset caused by moving the disk in either direction, but the depth varies to a different extent. When the disk moves parallel to the split, it is very suitable for the generation and evolution of the symmetric Fano resonance, particularly the structural symmetry of the split ring is further broken. As the disk moves perpendicular and closer to the split, the depth of each antisymmetric Fano resonance increases, while the appeared symmetric ones weaken. Such a nanostr...

中文翻译：

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椭圆盘-非同心裂环等离子体纳米结构中的对称和反对称多极电磁同声共振

提出了由非同心圆环中的椭圆形位移盘构成的等离子体纳米结构，并通过时域有限差分法进行了理论研究。模拟的散射光谱和电场分布表明，由于圆盘的纵向偶极子模式和裂环的多个多极子磁模式的相消干涉，可以形成多个Fano共振。还发现，每个Fano倾斜角的光谱位置对因在任一方向上移动磁盘而引起的偏移不敏感，但深度变化程度不同。当圆盘平行于裂口移动时，它非常适合对称Fano共振的产生和发展，尤其是裂口环的结构对称性会进一步破坏。当圆盘垂直移动并更接近分裂时，每个反对称Fano共振的深度都会增加，而出现的对称共振会减弱。这么纳米的...