Exciton energy transfer in hybrid organics – Semiconductor nanostructure

Abstract

We consider a hybrid heterostructure containing an inorganic quantum well in close proximity with an organic material as overlayer. The resonant optical pumping of Frenkel exciton can lead to an efficient indirect pumping of Wannier excitons. As organic material in such hybrid structure we consider crystalline tetracene. In tetracene diffusion length of singlet exciton diffusion is strongly dependent on temperature. We have obtained the exact analytical solution of diffusion equation for exciton in organics at different temperatures defining different diffusion lengths of excitons. Then we have included in consideration Coulomb interaction between organics and QW. It was shown that this interaction multiple increases effectiveness of transfer from organics to QW in the same way as it was predicted early in our publications for inverse transfer from QW to organics. The effectiveness of energy transfer in hybrid with tetracene was calculated by definite method for two selected temperatures that opens possibility to operate in full region of temperatures. Temperature dependence of energy transfer in organics opens a new possibility to turn on and off the indirect pumping due to energy transfer from the organic subsystem to the inorganic subsystem. This varying pumping may be used for experimental investigating of different nonlinear effects.