A sensitive 2D plasmon ruler based on Fano resonance

Abstract

In this paper, we designed a 2D distance and rotation angle plasmon ruler based on Fano resonance of a trimer nanostructure, which consists of a concentric square nanoring–disk and an outside nanorod (CSRDR).

Theoretical study on narrow Fano resonance of nanocrescent for the label-free detection of single molecules and single nanoparticles

“…[19][20][21][22][23][24] Fano resonances are drawing intense interest due to their promising applications in the optical imaging, switching, nonlinear and biochemical sensors. [25][26][27][28][29] Especially, they have been shown to be much more sensitive to the changes in geometry or local dielectric environment than the primitive modes of the nanostructure because of their microscopic origin as an interference phenomenon, which highly enhances the sensitivity of localized surface plasmon resonance sensors. For example, Cheng et al experimentally demonstrated ultrasensitive detection and characterization of molecules with an asymmetric infrared plasmonic metamaterial on account of a sharp Fano resonance.…”

“… 26 However, the significant role of absorption is neglected. 27 Strong radiative and nonradiative losses of plasmonic nanostructures will result in a broad line width, which can restrict the sensing performance. However, the radiation damping at Fano dip is very low, which gives rise to a very narrow resonance linewidth and is crucial for biosensing.…”

Magnetic Fano resonance of heterodimer nanostructure by azimuthally polarized excitation

“…Fano resonance based on artificial plasmon structure has become the focus of research in recent years for its wide applications in the areas such as surface enhanced Raman scattering (SERS) [1], slow-light devices [2], biological and chemical sensors [3,4], optical switch [5,6], and plasmon ruler [7]. Fano resonance, exhibiting an asymmetric line shape and inducing a large electromagnetic field enhancement [8,9], results from the interactions of narrow subradiant modes and broad superradiant modes.…”

High-precision measurement of plasmonic phase change in metal nanostructures

“…There are several plasmonic have been reported as a plasmonic ruler. For example, the gold sphere [155], a concentric square nanoring-disk and an outside nanorod [156],…”

“…We have succeeded to detect a 1.94 Å dynamic motion with an unprecedented 1.67 pm precision [183], therefore it is absolutely feasible to apply FCR plasmonic phase spectroscopy in the 2D plasmonic ruler. Several works are using SPP for 2D or 3D plasmon ruler [134,156], they are valuable references that can evaluate the effectiveness of our method. To demonstrate the feasibility of the hypothesis, a set of simulation was conducted with different pitch value (around 530 nm) in the X and Y-direction of the EOT sample (Fig.…”