Excitons in hybrid organic-inorganic nanostructures

In two-dimensional heterostructures made of semiconductor and organic layers, when resonance between the Wannier and Frenkel excitons is realized, the dipole-dipole interaction coupling them leads to novel effects. First, we discuss the pronounced nonlinear optical properties of the hybrid Frenkel-Wannier excitons appearing when the energy splitting of the excitonic spectrum is large compared to the exciton linewidths (the case of strong resonant coupling). Next, we consider the case of weak resonant coupling for which the Forster mechanism of energy transfer from an inorganic quantum well to an organic overlayer is of great interest: the electrical pumping of excitons in the semiconductor quantum well could be employed to turn on efficiently the organic material luminescence. (C) 1999 American Institute of Physics. [S1063-7834(99)00605-X].