Optical Microcavities: Single Virus Detection and Nanoparticle Trapping

摘要

Single polystyrene nanoparticles are detected from resonance wavelength fluctuations in toroidal and spherical microcavities. The magnitude of the wavelength-shift signal follows a reactive mechanism with inverse dependence on mode volume. By reducing the size of a microsphere cavity we demonstrate sensitivity to single Influenza A virions. Furthermore, we introduce a novel mechanism for trapping and accumulation of nanoparticles at the microcavity-sensor-region by utilizing light-force exerted in evanescent field gradients.