Towards an optical concentrator for nanoparticles

摘要

Photonic crystal (PC) biosensing platforms have the potential to achieve single-pathogen detection using nanoscale optical resonant cavities. Real-time sample analysis requires the PC sensor to be interfaced with a fluidic environment, but current practical fluidic structures typically have dimensions much larger than the PC sensing cavities. To enhance sensing probability, an on-chip optofluidic structure is being developed to concentrate target material within a narrow sensing region of the microfluidic channel. The device relies on fluid drag forces to propel material along the microfluidic channel. Dielectric material is guided transversely within the microfluidic channel by optical gradient forces due to the evanescent field surrounding a ridge waveguide within the channel. Results of computational modeling are presented.