High resolution UV spectral imaging and bio-detection with magnetic dipole quasi-BIC resonant dielectric metasurfaces

Abstract

In this paper, we designed a ring-shaped metasurface based on diamond material that response in ultraviolet band, and with which the BIC mode is obtained by breaking the symmetry of its structural units. We show that only when the radiation rate of the magnetic dipole resonance of the BIC mode is equal to the dissipation loss brought by the surface covering material, the interaction between light and matter is maximally enhanced. The absorptivity of the film material is enhanced by an order of magnitude. The simulation results show that there is a linear relationship between the resonant positions of the structure and the scaling factor S varying structure sizes. When the metasurface is covered with a single DNA film, changes differently due to the absorption of the DNA. The reflection information of the system is further converted into ultraviolet absorption of DNA. Then the multiple absorption peaks form the absorption spectrum of DNA molecules. By Arranging the different scaling factor metasurface pixels on a same substrate we can obtain a specific absorption image. The absorptivity of DNA leads to the difference in brightness and darkness of the metasurface pixels, which can be processed into gray-scale images that give out the specific fingerprint information of the DNA. So, we realized calibration and analysis of DNA without spectroscopic measurements in the ultraviolet band now. The metasurface device can effectively detect the contamination of DNA by other biomolecules such as RNA. This work has great significance in promoting the application of metasurfaces in the field of biological detection and demonstrates that a specially designed metasurface can be applied in nucleic acid detection.