Photon absorption in interacting quantum dots doped in nanofibers

Abstract

We study the coupling between quantum dots through the dipole–dipole interaction in photonic nanofibers manufactured by embedding a dielectric material into a photonic crystal. The embedded dielectric material is doped with an ensemble of three-level quantum dots. A probe field is applied to monitor the absorption, and a control field is applied to induce dipole moments in quantum dots. Dipoles are induced in quantum dots due to the external fields, and they interact with each other via the dipole–dipole interaction. Quantum dots also interact with the nanofiber through the electron–bound photon interaction. The absorption coefficient has been calculated using the density matrix method, and the dipole–dipole interaction has been evaluated in the mean field approximation. It is found that the absorption spectrum splits from one peak to two peaks by the dipole–dipole interaction. The splitting of peaks can be controlled by either the resonance energy of quantum dots or bound photon states of the nanofiber.