The mode splitting phenomenon in a high-quality whispering gallery mode(WGM)microresonator coupled to sub-wavelength scatterers can help resolve nanoparticle information.In this study,we analyzed the characteristics o...The mode splitting phenomenon in a high-quality whispering gallery mode(WGM)microresonator coupled to sub-wavelength scatterers can help resolve nanoparticle information.In this study,we analyzed the characteristics of nanoparticle-coupling-induced mode splitting,particularly in multiple-particle insertions relevant to practical biochemical sensing applications.The surface nanoscale axial photonics(SNAP)microresonator supports axial mode field distribution.We fabricated a fiber probe and used it to scan along the longitudinal axis of the SNAP microresonator,sequentially adjusting the axial mode to doublets,confirming the regulatability of mode splitting.The sensing region of the SNAP microresonator was immersed in particle-aqueous environments,and we observed mode splitting induced by particle scattering coupling.By analyzing splitting events,information such as particle binding number,average polarizability,and particle size can be resolved.The SNAP microresonator not only avoids interference from the detection environment on the coupling region through spatial separation between the coupling region and the sensing region,but also enables precise nanoparticle calculation based on splitting spectra,significantly enhancing the practicality of WGM microresonators in biochemical sensing applications.展开更多
基金National Natural Science Foundation of China(62465014,52465065,U24A20315)Natural Science Foundation of Jiangxi Province(20232BCJ23096,20232BAB212016,20232ACB212008,20242BAB25100,20203BBE53038,GJJ2401004).
文摘The mode splitting phenomenon in a high-quality whispering gallery mode(WGM)microresonator coupled to sub-wavelength scatterers can help resolve nanoparticle information.In this study,we analyzed the characteristics of nanoparticle-coupling-induced mode splitting,particularly in multiple-particle insertions relevant to practical biochemical sensing applications.The surface nanoscale axial photonics(SNAP)microresonator supports axial mode field distribution.We fabricated a fiber probe and used it to scan along the longitudinal axis of the SNAP microresonator,sequentially adjusting the axial mode to doublets,confirming the regulatability of mode splitting.The sensing region of the SNAP microresonator was immersed in particle-aqueous environments,and we observed mode splitting induced by particle scattering coupling.By analyzing splitting events,information such as particle binding number,average polarizability,and particle size can be resolved.The SNAP microresonator not only avoids interference from the detection environment on the coupling region through spatial separation between the coupling region and the sensing region,but also enables precise nanoparticle calculation based on splitting spectra,significantly enhancing the practicality of WGM microresonators in biochemical sensing applications.
