Recombination coefficients of GaN-based laser diodes

Abstract

We measure the charge carrier recombination coefficients of InGaN quantum wells by analyzing the dynamical properties of (Al,In)GaN laser diodes emitting in the violet spectral range. Relaxation oscillations and turn-on delays are fitted to a rate equation model including a charge carrier density dependent recombination rate. Using optical gain spectroscopy we can directly determine the injection efficiency of the devices and thereby separate the effect of charge carrier leakage from that of carrier recombination. We find a third-order recombination coefficient of (4.5±0.9)×10-31cm6s-1 which is in agreement with theoretical predictions for phonon- and alloy-disorder-assisted Auger scattering.