Plasmon-assisted transparency in metal-dielectric microspheres.

We present a theoretical analysis of light scattering from a layered metal-dielectric microsphere. The system consists of two spherical resonators coupled through concentric embedding. Solving for the modes of this system, we find that near an avoided crossing the scattering cross section is dramatically suppressed, exhibiting a tunable optical transparency. Similar to electromagnetically induced transparency, this phenomenon is associated with a large group delay, which in our system is manifest as flat azimuthal dispersion.