Influence of impurity concentration on the threshold characteristics of semiconductor lasers

The threshold characteristics of semiconductor lasers are considered as a function of the doping level and the temperature. Use is made of a model of the transitions from a parabolic conduction band to an impurity acceptor band with a Gaussian distribution of the density of states. The gain and the spontaneous recombination rate are calculated. The dependences of the threshold current, the quasi-Fermi levels, and the laser oscillation frequency on the impurity concentration and the temperature are obtained.