Interaction between radiation and a single excitonic state widely extended in a shell structure

Optical response of dielectric spheres with a semiconductor shell part confining the center-of-mass (c. m.) motion of excitons is studied. The self-consistent motions of radiation and excitons and nanoscale spatial structures of the coupled modes are considered. Microscopic calculation of nonlocal response is performed, which enables to incorporate the above elements into the calculation, considering both the transverse and longitudinal interactions between excitonic polarizations.