Ultra-Narrow Spectral Response of a Hybrid Plasmonic-Grating Sensor

Abstract

We configure and analyze a nanostructured device that hybridizes grating modes and surface plasmon resonances. The model uses an effective index of refraction that considers the volume fraction of the involved materials, and the propagation depth of the plasmon through the structure. Our geometry is an extruded low-order diffraction grating made of dielectric nano-triangles. Surface plasmon resonances are excited at a metal/dielectric interface, which is separated from the analyte by a high-index dielectric layer. The optical performance of the refractometric sensor is highly competitive in sensitivity and figure of merit (FOM) because of the the ultra-narrow spectral response (below 0.1 nm). Moreover, it is operative within a wide range of the index of refraction (from 1.3 till 1.56), and also works under normal incidence conditions.

All-Optical Nanosensor for Displacement Detection in Mechanical Applications

“…These resonant nanoparticles are not usually used in an individual way. On the contrary way, they are used to compose arrays or metasurfaces [27], taking advantage of not only the resonant nanoparticles but also other joint effects (e.g., diffractive modes) [28]. This kind of sensor provides ultra-high sensitivities and ultra-low detection limits with a small footprint and low power consumption making them ideal for the next sensing generation [29].…”

T-grating on a nano-cavity array based refractive index sensor

“…Over the past decade, a strong interest in plasmonic structures has been grown as extensive research has been conducted on perfect absorber [14][15][16], laser [17][18][19], label free biosensing [20][21][22], optical filter [23], nano-resonator [24], short range data transfer in photonic integrated circuits (PICs) [25], demultiplexer [26], buffer [24], polarizer [27] and refractive index sensor [28][29][30][31][32][33][34]. In SPR based refractive index (RI) sensors, phase matching condition for resonance can be satisfied by prism coupling or grating coupling [35].…”