Controlled emission from optical microdisk resonators perturbed by small scatterers

Optical microdisk resonators with circular boundaries support whispering gallery modes (WGMs) that travel along the boundary. These modes are formed by total internal reflection. Due to their extremely high Q-factors and small mode volumes they have found many applications in low-threshold lasing, the sensing of nanoparticles, optical filtering, nonlinear optics, etc.