Spectral and time resolved optical emission of a nonlinear dimer model

Abstract

The relations between the different stationary and nonstationary states of molecular excitations described by a nonlinear dimer model with cubic site polarization terms and the corresponding optical emission spectra are considered in detail. For the stationary states emission is explicitly calculated for both the symmetric case with equal optical coupling constants of both molecules constituting the dimer as well as the asymmetric case where one of the molecules is optically active only. The time-resolved emission from the nonstationary states is treated by using a quasistationary approximation based on slow transfer dynamics compared to the polarization. Of particular interest in the nonstationary case is the chaotic transfer regime induced by a harmonic perturbation. For the latter case the evolution of the spectrum from an ensemble of dimers spreading within the stochastic layer on the Bloch sphere is presented.