Sablikov. Light-induced charge carriers lateral transfer in heterostructures with 2D electron gas

Nonequilibrium electron processes in semiconductor heterostructures with 2D electron gas are considered. A model of light-induced charge carriers transfer is developed which allows one to describe local optical excitation effect on heterostructures. The model is based on separation of the heterostructure electron system into two subsystems: electrons in the volume of active layer and 2D electrons localized in a quantum well. The coupling of these subsystems is described by kinetic coefficients introduced into both the boundary conditions for equations describing the volume electrons and the transport equation for 2D electrons. The electron transport in the volume and along the quantum well is described in the frame of drift-diffusion approximation. Together with the general formulation of the problem, ID transfer of electrons and holes crosswise the active layer in the case of homogeneous light excitation was considered and numerical simulation of the process was carried out. Analysis of numerical results allowed to determine conditions when the electron and hole concentrations have the quasi equilibrium distributions. In this situation the general characteristics of light-induced charge carriers transfer along an active layer can be defined by using ID model.