Numerical study of sensitivity enhancement in a photonic crystal microcavity biosensor due to optical forces.

Photonic crystal microcavity biosensors can detect single biomolecules, but reliance on diffusion from microfluidic flow for particle delivery limits the minimum detectable particle concentration. Here the particle equation of motion is solved to find the sensitivity enhancement due to optical forces. The enhancement is examined for a range of parameters, including input optical power, fluid flow rate, device quality factor, and particle size.