Simulation of transient and spatial structure of the radiative flux produced by multiple recombinations of excitons

Abstract In this paper, we study the multiple recombination exciton–photon–exciton process governed by a coupled system of the drift-diffusion-recombination equation and the integral radiative transfer equation. We develop a random walk on spheres algorithm for solving this system of equations. The algorithm directly simulates the transient drift-diffusion process of exciton’s motion. Then, at a random time the exciton recombines to a photon that moves in accordance with the radiative transfer equation, which in turn may recombine to an exciton etc. This algorithm is applied to calculate fluxes of excitons and photons as functions of time, and some other characteristics of the process. Calculations have also been carried out to validate the constructed model.