High-Q-value metasurface refractive index sensor based on connection of double semicircular ring holes

Abstract

The invention discloses a high-Q-value dielectric metasurface refractive index sensor based on connection of double semicircular ring holes, and the optical refractive index sensor is mainly composed of a dielectric substrate and a metasurface microstructure unit array. the dielectric metasurface structure unit array is composed of a plurality of micro-structure units, two connecting semicircular holes are etched in each dielectric metasurface micro-structure unit in a central symmetry mode, and the radiuses of the inner circle and the outer circle of the two connecting semicircular holes are both R1 and R2. When light waves are vertically incident, a sharp Fano resonance is formed in a transmission spectrogram of the device and can be used for a refractive index sensor. The sensor is made of an all-dielectric material, has no ohmic loss, shows a relatively high Q value, and can be used for detecting gases and liquids with different refractive indexes.

Description

technical field [0001] The invention relates to the field of micro-nano optical sensing, in particular to a high-Q metasurface refractive index sensor based on connecting double semicircular holes. Background technique [0002] Optical refractive index sensors are widely used in the measurement of refractive index in physical chemistry, biomedicine, food processing, etc., and have attracted extensive attention from researchers. Usually, the sensitivity of a refractive index sensor is defined as the change of resonance wavelength per unit refractive index, namely: S=Δλ / Δn. In addition, the Q value of the resonant cavity is another important parameter for evaluating optical refractive index sensors. High-Q resonators are easier to detect and easier to integrate. At present, people's research on the refractive index sensor mainly focuses on the metal-based plasmonic structure. However, due to the strong radiation loss caused by the free electron oscillation in the metal struc...

AI Technical Summary

Problems solved by technology

At present, people's research on the refractive index sensor mainly focuses on the metal-based plasmonic structure. However, due to the strong radiation loss caused by the free electron oscillation in the metal structure, the Q value of the metal structure is usually low, which limits the metal-based plasmonic structure. Applications of Plasmonic Structured Devices in Nanophotonics

Images