Exciton hybridization states in organic–semiconductor heterostructures containing quantum dots

Nguyen Que Huong

Abstract

The formation of a hybridization state of Wannier Mott and Frenkel excitons is theoretically studied for different heterostructure configurations involving quantum dots. At the interfaces of the semiconductor quantum dots and the organic medium, the hybridization states are formed, having complimentary properties of both kinds of excitons as well as large optical nonlinearities. The coupling at resonance is very strong, depending on the parameters of the systems (dot radius, dot separation, generation of the organic dendrites and the materials of the systems, etc). The hybrid excitons are as sensitive to external perturbation as Wannier–Mott excitons. Upon the application of magnetic and electric fields, the coupling term between the two kinds of excitons increases. The most important feature of this system is that by adjusting the system parameters as well as the external fields and their orientation, one can tune the resonance between the two kinds of excitons to get different regions of mixing to obtain the expected high nonlinearity