Controllable optical response of the metal nanoparticle–quantum dot–metal nanoparticle hybrid nanosystem due to the plasmon–exciton–plasmon coupling effect

The optical response of the hybrid nanosystem composed of two metallic nanoparticles (MNPs) and a semiconductor quantum dot (SQD) is investigated theoretically due to the plasmon–exciton–plasmon coupling effects, which depend on the interaction between the induced dipole moments in the SQD and the MNPs, respectively. We show that the strong coupling of excitons and localized surface plasmons in such a nanosystem leads to appealing, tunable optical properties by adjusting the symmetry of the MNP–SQD–MNP hybrid system with controllable interparticle distances. We also address here the influence of the size of the MNPs (which affects the G-parameter) and the dielectric constant of the background medium (which affects the environment-dependent dielectric screening effect) on the dual dipole–dipole interactions of the MNPs and SQD, respectively, which result in the interparticle Förster resonance energy transfer. Our results will open an avenue to deal with surface-enhanced spectroscopies and potential application of quantum information.