Modeling of temperature and excitation dependences of efficiency in an InGaN light-emitting diode.

The changes in excitation dependence of efficiency with temperature are modeled for a wurtzite InGaN light-emitting diode. The model incorporates bandstructure changes with carrier density because of screening of quantum-confined Stark effect. Bandstructure is computed by solving Poisson and k · p equations in the envelope approximation. The information is used in a dynamical model for populations in momentum-resolved electron and hole states. Application of the approach shows the interplay of quantum-well and barrier emissions giving rise to shape changes in efficiency versus current density with changing temperature, as observed in some experiments.