Giant Electric Field Enhancement and Localized Surface Plasmon Resonance by Optimizing Contour Bowtie Nanoantennas

Abstract

The surface plasmon resonances of gold contour bowtie nanostructures were simulated in the present study. The local electromagnetic field enhancement and the resonance wavelength for different dimensions of contour bowtie antennas with various contour thicknesses were investigated to find the critical conditions to induce additional enhancement compared to the solid bowtie antenna. Both the phase of the electric field and the bound surface charge distribution on the surface of the contour bowtie were studied to characterize the coupled plasmon configurations of the contour bowtie antenna. Also, a model was proposed to explain the resonance and hybridization behavior in the contour bowtie nanoantenna, and it was verified by examining the phase of the electric field in the polarization direction.

Optimized Sensitivity and Electric Field Enhancement by Controlling Localized Surface Plasmon Resonances for Bowtie Nanoring Nanoantenna Arrays

“…However, there are few reports [24] on the advantages of combining the great electromagnetic field enhancement produced in the bowtie-shaped antenna gap with the enhanced sensitivity characteristic of the nanoring structure. Although a contour bowtie antenna model has been proposed and it showed the electromagnetic field enhancement [25][26][27], the mechanism of the bowtie nanoring antenna with different nanohole sizes inside the bowtie antenna to increase the sensitivity by the nanohole structure has not yet been investigated.…”

Surface plasmon-enhanced fluorescence on Au nanohole array for prostate-specific antigen detection

“…[12][13][14] Surface plasmons (SPs) with field E SP excited by an incoming light E 0 can enhance fluorophore excitation rate and Raman scattering by factors up to |E sp /E 0 | 2 and |E sp /E 0 | 4 , respectively. [15][16][17][18] Various metal nanostructures have been reported for the enhancement of fluorescence emission, such as nanoholes, [19][20][21] nanorods, 22,23 core-shell nanoparticles, [24][25][26] bowtie nanoantennas, 27,28 DNA-assembled nanoparticles, 29 and antennas-in-box. 30 The SPFS based on metallic thin film is usually achieved with Kretschmann configuration by coupling evanescent waves with SPs, which has been reported for highly sensitive detection of biomolecules including biomarkers, 31,32 toxins, and oligonucleotides, 33 with the limit of detection (LOD) down to attomolar range.…”

Free-standing gold elliptical nanoantenna with tunable wavelength in near-infrared region for enhanced Raman spectroscopy

“…Localized surface plasmon has been widely used on surface-enhanced Raman spectroscopy (SERS) [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Coupling between two metal surfaces separated by few nanometers brings localized surface plasmon to resonate at the gap and induces large electromagnetic field enhancement.…”

“…The resonance wavelength is strongly dependent on the geometry of the antenna, and the enhancement factor can be manipulated by the gap distance [1] or the corner radius [17]. Recently, the enhancement factor has shown the dependence on the column and row distances of the periodic nanostructure due to the long-range resonance between each individual bowtie antenna [2][3][4][5]. The maximum enhancement can be achieved as the periodic distance in the polarization direction matches the incident wavelength for the bowtie structure [6].…”