Nanoscale microcavity sensor for single particle detection

Recently we demonstrated a biosensor based on a two-dimensional photonic crystal microcavity for detection of proteins. We present a theoretical and experimental study of a modified structure for single particle detection. With an active sensing volume of similar to 0.15 mu m(3), the device is capable of detecting similar to 1 fg of matter. Its performance is tested with latex spheres with sizes that fall in the size range of a variety of viruses. (c) 2007 Optical Society of America.