Hybridization theory between localized mode and free propagating modes for light scattering from a dielectric sphere

Light scattering from a homogeneous dielectric sphere is discussed in terms of hybridization between a localized mode excited inside the dielectric sphere and free propagating modes in vacuum. This theory is a photonic counterpart of the Anderson model in electron systems, yielding a rigorous theoretical foundation of the heavy photon concept, which was numerically proposed for almost flat photonic bands. The magnitude of the hybridization is analytically expressed. The localized mode is identified with the photon virtual bound state. In order to confirm the validity of the present theory, a comparison is made between the present theory and conventional numerical calculation for results of the photonic density of states.