Polarimetric Plasmonic Sensing with Bowtie Nanoantenna Arrays

Abstract

We propose a polarimetric plasmonic biosensor based on bowtie nanoantenna array transducers. Through numerical simulations, based on the Finite Element Method (FEM), we study the phase retardation between the components of light polarized parallel and perpendicular to the major axis of the bowties within the arrays. From a design for high volumetric sensitivity at a wavelength of 780 nm, sensitivities ~5 rad/RIU is obtained, corresponding to a detection limit of ~10-7 when using a polarimetric readout platform. Similarly, surface sensitivity of the same array is evaluated by simulating the phase retardation changes induced by the coverage of bioreceptors and analytes of the metallic nanostructures.

Integration of bow-tie plasmonic nano-antennas on tapered fibers

“…measurement to demonstrate an application for the nano-antenna array on the tapered fiber. Besides that, it would be possible to measure sensitivities experimentally on the magnitude order predicted by Calderón and colleagues [31] and our device is more compact compared to long periodic gratings based sensitivity devices [32]. Moreover, it would also be possible to improve the sensitivity figure by placing a circular hole within the bowtie nano-antenna triangular element as demonstrated by Nien et al [33].…”

All-Opto Plasmonic-Controlled Bulk and Surface Sensitivity Analysis of a Paired Nano-Structured Antenna with a Label-Free Detection Approach

“…In this work, an FEM-based frequency domain approach [8,11,18,19,30,31] was used to determine the plasmonic field distribution of gold nanoparticles. Figure 1 shows the dimensions of the nanostructures, where a and b are the major and minor axes, h is the height, and the separation gap is g. The schematic diagram of a paired gold nanostructured antenna on a quartz substrate is shown in Figure 1a, the unit cell of the quartz substrate on which a paired gold nanostructure was placed.…”

“…Nanoantennas are used for Surface-Enhanced Raman Spectroscopy (SERS), which have the advantage of resonating simultaneously both in the infrared and visible regions [7]. Additionally, paired nanoantennas of different shapes such as bow-tieshaped [8][9][10][11], nanodiscs [12][13][14], nanorods [10,[15][16][17], and elliptical nanoantennas have been reported [18,19] for the visible region. In 2008, Fisher and Martin reported [20] a sensitivity of 500-510 nm/RIU for a bow-tie-shaped plasmonic nanoantenna with a 10 nm gap between the sharper 20 nm tips.…”

“…The above discussions show the promising results of strong resonance and field confinement through numerical modelling and experimental investigations. Recently, the numerical design and simulation of gold nanoantennas was modelled by a computationally efficient Finite Element Method (FEM) [8,11,18,19,30,31] and the versatile Finite Difference Time Domain method (FDTD) [32][33][34][35][36].…”

Resonance spectra of diabolo optical antenna arrays

“…[6][7][8] Earlier studies have been focused on bowtie optical antennas with different shapes of metal patches and apertures. [9][10][11][12][13][14][15][16][17][18][19][20] Recently, rectangular metal bar optical antenna arrays have been investigated due to the easy tuning of the resonance wavelength and near-field spatial distributions through modifying antenna bar length, array period, and substrate. [21][22][23][24][25][26][27] A diabolo antenna is a variation of a rectangular metal bar antenna with reduced waist width.…”