@conference{10902/28361,
year = {2022},
month = {3},
url = {https://hdl.handle.net/10902/28361},
abstract = {All-dielectric metasurfaces have attracted increasing attention due to their negligible losses and sharper resonances compared to their metallic counterparts. In this work, we numerically studied the optical performance of a novel alldielectric metasurface based on complementary split-ring resonators (CSRRs), in which ultrathin slots were periodically etched in a thin silicon layer. The proposed CSRR metasurface exhibits two multipolar resonances in the near-infrared (NIR) window. Moreover, a quasi-bound state in the continuum (quasi-BIC) with an ultra-high quality factor can be excited by breaking the symmetry of the structure. Taking advantage of the high-quality factor quasi-BIC mode and its sensitivity to the superstrate medium refractive index (S = [Di] res/[Dn]), we design an ultra-high figure of merit (FoM = S/FWHM) refractive index sensor for biomedical applications. By three-dimensional finite element method (3D-FEM), we evaluate the sensitivity of the sensing device to the variation of the superstrate refractive index in the range 1.31-1.33, which is typical for aqueous solutions. Our simulations reveal that a sensitivity of S ~ 155 nm RIU-1 and an extraordinary FoM ~ 387500 RIU-1 can be achieved using the ultra-narrow quasi-BIC resonance in the CSRR metasurface structure. The proposed approach opens new paths to develop flat biochemical sensors with high accuracy and real-time performance.},
publisher = {SPIE Society of Photo-Optical Instrumentation Engineers},
publisher = {Proceedings of SPIE, 2022, 11987, 119870B},
publisher = {Laser Resonators, Microresonators, and Beam Control XXIV, 2022, San Francisco},
title = {Refractive index sensing by all-dielectric metasurfaces supporting quasi-bound states in the continuum},
author = {Samadi, Mohsen and Abshari, Fatemeh and Algorri Genaro, José Francisco and Roldán Varona, Pablo and Rodríguez Cobo, Luis and López Higuera, José Miguel and Sánchez Pena, José Manuel and Zografopoulos, Dimitrios C. and Dell'Olio, Francesco},
}