Abstract

Optical microcavity biosensing has emerged as one of the most sensitive detection technologies. We report a new label-free detection method of single nanoparticles by employing nanoparticle-scattering-induced mode broadening in a free-space-coupled deformed microcavity. By monitoring the change of resonance linewidth, our method transcends the detecting ability limited by the intrinsic resonance linewidth and demonstrates the biosensing ability to detect single lentiviruses.

© 2013 Optical Society of America