A detection method for local environment based on strong coupling of core-shell nanoparticles

Abstract

The invention provides a method for detecting a localized environment based on core shell structure nanoparticle strong coupling. The method comprises a step a) of designing a localized surface plasmon resonance (LSPR) nanoparticle sensor of a core shell structure, wherein after the strong coupling of the LSPR nanoparticle sensor, two peaks of a split extinction cross-section of the LSPR nanoparticle sensor in water are symmetric; a step b) of obtaining relations of two-peak strong of strong coupling splitting varying with a localized environment refractive index around the sensor; a step c) of obtaining a two-peak strength ratio, wherein the ratio is the value obtained by dividing the strength of the peak with a long wavelength by the strength of the peak with a short wavelength and the ratio has a specific law for the variation of the localized environment refractive index; a step d) of fitting the ratio according to the law into a function with respect to the localized environment refractive index; a step e) of detecting a to-be-detected surrounding localized environment according to the law and the fitting function thereof, substituting the measured strength ratio of the spectrum split peak into the fitting function to perform calculation, and obtaining a value of the localized environment refractive index.

Description

technical field [0001] The invention belongs to the field of optical spectrum measurement, in particular to a method for detecting local environment based on strong coupling of core-shell nanoparticle. Background technique [0002] In the 1960s, a perfect theory for explaining surface plasmon resonance appeared, and after that, the research on surface plasmon resonance increased day by day, and its application was very extensive. For very small nanoparticles, surface plasmon resonance cannot form a propagating mode, called localized surface plasmon resonance (LSPR), which has special optical properties. The localized surface plasmon characteristics of metal nanoparticles are mainly reflected in the relationship between their optical cross-section and wavelength. For the position of the surface plasmon resonance peak on the wavelength, the full width at half maximum of the peak and the intensity of the peak, these parameters mainly depend on the metal The dielectric constant...

AI Technical Summary

Problems solved by technology

All in all, very few existing LSPR sensors use peak intensity changes for detection

Images