Monte Carlo algorithms for collisional broadening and intracollisional field effect in semiconductor high-field transport

Abstract

We present a computational scheme which can be readily included in a standard Monte Carlo code to give quantitative estimates of the intracollisional field effect (ICFE) or of collisional broadening (CB). The central quantity in our theory is the joint spectral density K(εi, εf ) which connects the initial and final kinetic energy of a carrier in a scattering event. Crucial approximations, connected with the algorithms which model the joint spectral densities obtained from the appropriate Dyson equation, are clearly stated and discussed. Numerical results for a simple model semiconductor are provided for illustrative purposes. These show that both ICFE and CB lead to a significant increase of carriers in the high-energy tail of the distribution function.