Spherical whispering-gallery-mode resonators as detectors of nanoparticles: theory and comparison with experiment

During the last decade significant experimental efforts were devoted to developing detectors of nanosized -objects using whispering-gallery-mode resonances. The ultimate goal of these efforts is to achieve detection and determination of the size of a single protein. In this talk I will present recent developments concerning theoretical description of particle-induced modifications of whispering-gallery-modes both in strong and weak coupling regimes. Comparison of the theory with experimental data and ways to improve sensitivity of detection will be discussed.