Analysis of coherent and incoherent ultrafast dynamics in photoexcited semiconductors: a Monte Carlo approach

In the present paper we present a generalized Monte Carlo method recently developed by the authors for the solution of the coupled set of quantum kinetic equations for the distribution functions and the interband polarization. The aim of this method is to combine the advantages of the description within a fully quantum mechanical picture with the power of the Monte Carlo technique for the treatment of stochastic processes. It is based on a decomposition of the kinetic equations into a coherent and an incoherent part. The former is integrated directly while the latter is solved by means of a Monte Carlo simulation. Band renormalization and excitonic effects are included in a self-consistent way. The calculations allow us to treat carrier thermalization and relaxation, as well as the dephasing process, on the same level.