Localized light in a multiple photonic quantum well system

Localization of light in a basic multiple photonic quantum well system (MPQWS) is investigated with the finite-difference time-domain method. Resonance tunneling and splitting are observed in a MPQWS, as electron waves to a superlattice. Our numerical results reveal a quite interesting hierarchic distribution of the field mode when the system is illuminated with plane waves at a specific frequency. That is, if the number of wells is odd (even), strong localized states occur in odd (even) indexed wells. Light localization in a MPQWS, however, seems to be confined only in a narrow incident frequency window.