A high figure of merit localized surface plasmon sensor based on a gold nanograting on the top of a gold planar film

Abstract

We investigate the sensitivity and figure of merit (FOM) of a localized surface plasmon (LSP) sensor with gold nanograting on the top of planar metallic film. The sensitivity of the localized surface plasmon sensor is 317 nm/RIU, and the FOM is predicted to be above 8, which is very high for a localized surface plasmon sensor. By employing the rigorous coupled-wave analysis (RCWA) method, we analyze the distribution of the magnetic field and find that the sensing property of our proposed system is attributed to the interactions between the localized surface plasmon around the gold nanostrips and the surface plasmon polarition on the surface of the gold planar metallic film. These findings are important for developing high FOM localized surface plasmon sensors.

Near Infrared Metal-insulator-metal Surface Plasmon Resonances for Refractive Index Sensors

“…The resonance redshifts linearly as the refractive index of the cladding material increases and the sensitivity is the change of wavelength over the change of the refractive index and is calculated to be 370 nm/RIU. This obtained sensitivity in our proposed MIM gold-micro disk array can be comparable with the sensitivity achieved in other gold nano-structured configurations[20,21].…”

“…With the aim to target the bio-applications, sensors operate in near infrared where the fluorescent molecules emit, are of interest, because in these regions the absorption of water or other bio-materials are low. However, SPR-MIM sensors have been widely investigated using the metallic patterns of nanometers [19][20][21]. The sensing behavior of the SPR-MIM sensors in which employing the micro metallic pattern arrays have rarely been studied.…”

Plasmonic Refractive Index Sensors Based on One- and Two-Dimensional Gold Grating on a Gold Film

“…Under the optimized geometric parameters, the diffraction caused by the nano-grating can compensate for the appropriate optical momentum to achieve the effective coupling between the incident light and the surface plasmons, thereby exciting the strongly propagating surface plasmon resonances. In addition, the nano-grating in the sensing structure can be either dielectric or metallic [50][51][52], and the metal nano-grating can generally excite more surface plasmon resonance modes. When surface plasmon resonances are used for refractive index sensing, propagating surface plasmons have more advantages than local surface plasmons.…”

“…The resonance peak excited by the propagating surface plasmons usually has a narrower full width at half maximum (FWHM), which means a higher figure of merit (FOM) and a refractive index resolution. In the literature, there have been many reports on surface plasmon refractive index sensors excited by one-dimensional (1D) gratings [50][51][52].…”

Deep-ultraviolet surface plasmon resonance of Al and Alcore/Al2O3shellnanosphere dimers for surface-enhanced spectroscopy

“…Localized surface plasmon resonance (LSPR) in metallic nanostructures originates from the collective oscillation of free conduction electrons in metal surface when interacting with light, which is highly sensitive to the metal composition, shape, size, and surrounding environment. [1,2] Due to the high ability to enhance and concentrate electric fields down to nanometer scale, LSPR of metallic nanostructures has a wide range of applications in plasmonic photovoltaic cells, [3] surface-plasmon enhanced spectroscopies, [4][5][6][7][8] photochemistry, [9,10] sensing, [11,12] photodetectors, [13] and quantum optics. [14][15][16] Plasmonic properties in these applications were usually carried out with noble metals Au and Ag, where LSPR is limited in the visible and near-infrared (NIR) light regions due to damping in the ultraviolet (UV) and deep-ultraviolet (DUV) regions caused by the interband transitions.…”