Quantum Dot Lattice Embedded in An Organic Medium: Hybrid Exciton State and Optical Response

Nguyen Que Huong; Joseph L. Birman

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arXiv · cond-mat/9812307

Quantum Dot Lattice Embedded in An Organic Medium: Hybrid Exciton State and Optical Response

Nguyen Que Huong·Joseph L. Birman

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Abstract

We propose a new model to implement organic exciton-semiconductor exciton hybridization by embedding a semiconductor quantum dot array into an organic medium. A Wannier-Mott transfer exciton is formed when the exciton in each semiconductor dot interacts via the multipole-multipole coupling with other excitons in the different dtos of the array. A new hybrid exciton appears in the system owing to strong dipole-dipole interaction of the Frenkel exciton of the organic molecules with the Wannier Mott transfer exciton of the quantum dot array. This hybrid exciton has both a large oscillator strength (Frenkel like) and a large Bohr radius (Wannier like). At resonance between these two types of excitons, the optical non-linearity is very large and can be controlled by changing parameters of the system such as dot radius and dot spacing.

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Nguyen Que Huong, Joseph L. Birman. 1999-12-14. Quantum Dot Lattice Embedded in An Organic Medium: Hybrid Exciton State and Optical Response. https://arxiv.org/abs/cond-mat/9812307

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