Effect of doping concentration on the peak wavelength of photoluminescence in donor-acceptor systems

Efficient donor-acceptor (DA) energy transfer material systems are considered to be the candidate for organic lasers. We developed a numerical model for the emission spectra of DA systems based on the theory of Förster energy transfer and stimulated emission. The model describes the essential emission spectrum features related on the acceptor concentration in theoretical DA system, in which the monomer wavelength of the photoluminescence increases none linearly with the acceptor concentration, and tends to reach the monomer emission wavelength of acceptor at high acceptor concentration.