Advanced terahertz refractive index sensor in all-dielectric metasurface utilizing second order toroidal quasi-BIC modes for biochemical environments.

ABSTRACT: We present a novel design for an all-dielectric metasurface ultra-sensitive refractive index (RI) sensor, characterized by a high-quality factor (Q_f) and figure of merit (FOM). This design incorporates two high-order toroidal modes, including electric toroidal quadrupole ([Formula: see text]​) and magnetic toroidal quadrupole ([Formula: see text]​) based on quasi‑bound states in the continuum (q-BIC) resonances. Our findings demonstrate the feasibility of switching between [Formula: see text] and [Formula: see text]​ through various symmetry-breaking mechanisms. To excite these high-order toroidal modes, we explored several symmetry-breaking strategies, including complex structural designs, symmetry disruption, and variations in the incident wave angle. Symmetry breaking in the

SUBMITTER: Maleki J 

PROVIDER: S-EPMC11489418 | biostudies-literature | 2024 Oct

REPOSITORIES: biostudies-literature