Threshold characteristics of InGaAsP/InP multiple quantum well lasers

A theoretical analysis and computer simulation of the threshold current density j th and characteristic temperature T 0 of multiple quantum well lasers (MQWLs) are presented. Together with the spontaneous radiative recombination, the Auger recombination and the lateral diffusive leakage of carriers from the active region are included into the model. A first-principle calculation of the Auger recombination current is performed. It is shown that the lateral diffusive leakage current is controlled by the radiative and Auger currents. When calculating the carrier densities, the electrons in the barrier regions are properly taken into account. Redistribution of electrons over the active region is shown to increase the threshold current considerably. The dependences of j th and T 0 on temperature, number of QWs, cavity length and lateral size are discussed in detail. The effect of lattice and carrier heating on j th and T 0 is investigated and shown to be essential at high temperature.