Dielectric particle trimer: enhanced sensing of environmental changes through coupled Mie resonances

Coupled Mie resonance via a symmetrical block-particle trimer is proposed to significantly enhance near-field interactions for sensing the ambient changes. Unlike the resonances of individual particles and dimers, both the frequency and strength of the enhanced magnetic and electric dipole resonances in the trimer exhibit excellent linear responses and high sensitivities, particularly for the electric dipole mode. The cube-like particles strengthen the Mie resonances coupling with distinct anisotropic energy distributions. The symmetrical structure of the trimer overcomes the issue of splitting electric dipole resonance observed in dimers. Experiments demonstrate that the trimer-based waveguide sensor provides real-time in situ monitoring and delivers more valuable information compared to traditional methods. It offers a cost-effective and miniaturized approach for real-time detect the environmental refractive index and monitoring its dynamic change process. Additionally, the trimer shows broad applicability across diverse fields such as environmental protection, biomedicine, process control, and scientific research. Overall, the coupled Mie resonances of this trimer establish a versatile photonic platform to enhance light-matter interactions and open up new possibilities for precise spectroscopic detection.